[Bug] Crash on start up

Please note that we do not provide support for clients other than Forge. We will not fix compatibility issues with other clients.
Describe the bug Crashes on startup.
To Reproduce Build beta 7 from development branch
Expected behavior Should have launched
Crash Report If your game crashed, please paste your crash report below.
WARNING: coremods are present:
  FMLLoadingPlugin (Scrollable Tooltips-1.3 (1.8.9).jar)
  SkyblockAddonsLoadingPlugin (SkyblockAddons-1.6.0-beta.7-for-MC-1.8.9.jar)
  PatcherTweaker (Patcher-1.5.1 (1.8.9).jar)
  ModTweaker (Patcher-1.5.1 (1.8.9).jar)
Contact their authors BEFORE contacting forge

// This doesn't make any sense!

Time: 14/02/21 11:09
Description: There was a severe problem during mod loading that has caused the game to fail

net.minecraftforge.fml.common.LoaderException: java.lang.NoSuchMethodError: com.google.gson.JsonParser.parseString(Ljava/lang/String;)Lcom/google/gson/JsonElement;
    at net.minecraftforge.fml.common.LoadController.transition(LoadController.java:162)
    at net.minecraftforge.fml.common.Loader.initializeMods(Loader.java:744)
    at net.minecraftforge.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:310)
    at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:495)
    at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:329)
    at net.minecraft.client.main.Main.main(SourceFile:124)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
Caused by: java.lang.NoSuchMethodError: com.google.gson.JsonParser.parseString(Ljava/lang/String;)Lcom/google/gson/JsonElement;
    at codes.biscuit.skyblockaddons.utils.Utils.loadLanguageFile(Utils.java:662)
    at codes.biscuit.skyblockaddons.utils.Utils.loadLanguageFile(Utils.java:645)
    at codes.biscuit.skyblockaddons.config.ConfigValues.loadValues(ConfigValues.java:243)
    at codes.biscuit.skyblockaddons.SkyblockAddons.postInit(SkyblockAddons.java:140)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at net.minecraftforge.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:560)
    at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
    at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
    at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
    at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
    at com.google.common.eventbus.EventBus.post(EventBus.java:275)
    at net.minecraftforge.fml.common.LoadController.sendEventToModContainer(LoadController.java:211)
    at net.minecraftforge.fml.common.LoadController.propogateStateMessage(LoadController.java:189)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
    at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
    at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
    at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
    at com.google.common.eventbus.EventBus.post(EventBus.java:275)
    at net.minecraftforge.fml.common.LoadController.distributeStateMessage(LoadController.java:118)
    at net.minecraftforge.fml.common.Loader.initializeMods(Loader.java:742)
    ... 10 more

A detailed walkthrough of the error, its code path and all known details is as follows:
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-- System Details --
Details:
    Minecraft Version: 1.8.9
    Operating System: Windows 10 (amd64) version 10.0
    Java Version: 1.8.0_51, Oracle Corporation
    Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
    Memory: 276553000 bytes (263 MB) / 1260912640 bytes (1202 MB) up to 3817865216 bytes (3641 MB)
    JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx4G
    IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
    FML: MCP 9.19 Powered by Forge 11.15.1.1722 Optifine OptiFine_1.8.9_HD_U_M5 13 mods loaded, 13 mods active
    States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored
    UCHIJ   mcp{9.19} [Minecraft Coder Pack] (minecraft.jar) 
    UCHIJ   FML{8.0.99.99} [Forge Mod Loader] (forge-1.8.9-11.15.1.1722.jar) 
    UCHIJ   Forge{11.15.1.1722} [Minecraft Forge] (forge-1.8.9-11.15.1.1722.jar) 
    UCHIJ   autotip{3.0.1} [Autotip] (Autotip-3.0.1 [1.8-1.12.2].jar) 
    UCHIJ   modcore{0.1.47} [ModCore] (Sk1er Modcore-0.1.47 (1.8.9).jar) 
    UCHIJ   Danker's Skyblock Mod{1.8.4} [Danker's Skyblock Mod] (1.8.9.Danker.s.Skyblock.Mod.-.1.8.4.jar) 
    UCHIJ   sidebarmod{2.0} [Sidebar Mod Revamp] ([1.8.9] Sidebar Mod Revamp.jar) 
    UCHIJ   konkrete{1.1.3} [Konkrete] (konkrete_1.1.3_MC_1.8.9.jar) 
    UCHIJ   fancymenu{1.6.0.1} [FancyMenu] (fancymenu_1.6.0.1_MC_1.8.9.jar) 
    UCHIJ   patcher{1.5.1} [Patcher] (Patcher-1.5.1 (1.8.9).jar) 
    UCHIJ   scamprotect{1.2.6} [ScamProtect for 1.8.9] (scamprotect-1.8.9-1.2.6.jar) 
    UCHIJ   text_overflow_scroll{1.3} [Scrollable Tooltips] (Scrollable Tooltips-1.3 (1.8.9).jar) 
    UCHIE   skyblockaddons{1.6.0-beta.7} [SkyblockAddons] (SkyblockAddons-1.6.0-beta.7-for-MC-1.8.9.jar) 
    Loaded coremods (and transformers): 
FMLLoadingPlugin (Scrollable Tooltips-1.3 (1.8.9).jar)
  club.sk1er.mods.overflowscroll.forge.ClassTransformer
SkyblockAddonsLoadingPlugin (SkyblockAddons-1.6.0-beta.7-for-MC-1.8.9.jar)
  codes.biscuit.skyblockaddons.tweaker.SkyblockAddonsTransformer
PatcherTweaker (Patcher-1.5.1 (1.8.9).jar)
  club.sk1er.mods.core.forge.ClassTransformer
  club.sk1er.patcher.tweaker.ClassTransformer
ModTweaker (Patcher-1.5.1 (1.8.9).jar)
  club.sk1er.patcher.tweaker.other.ModClassTransformer
    GL info: ' Vendor: 'ATI Technologies Inc.' Version: '4.6.14757 Compatibility Profile Context 20.11.2 27.20.14501.18003' Renderer: 'AMD Radeon RX 5700 XT'
    OptiFine Version: OptiFine_1.8.9_HD_U_M5
    OptiFine Build: 20210124-163719
    Render Distance Chunks: 8
    Mipmaps: 4
    Anisotropic Filtering: 1
    Antialiasing: 0
    Multitexture: false
    Shaders: null
    OpenGlVersion: 4.6.14757 Compatibility Profile Context 20.11.2 27.20.14501.18003
    OpenGlRenderer: AMD Radeon RX 5700 XT
    OpenGlVendor: ATI Technologies Inc.
    CpuCount: 12
System Information
OS: Windows 10
Minecraft Version: 1.8.9
Forge Version: Both 11.15.1.2318 & 11.15.1.1722
SkyblockAddons Version: Beta 7
Other Installed Mods I have tried to launch it without the mods I have installed but the same problem occours
BiscuitDevelopment / SkyblockAddons

[Bug] Crash on start up #503
