Check if installer uses InstallerV1 while spec is 0

[Pierce01]

Fixes the following error when trying to launch from a fresh install.

Error is caused by spec being defined as 0 while using InstallV1

Missing: C:\Users\pierc\OneDrive\Desktop\Coding\minecraft1\libraries\net\minecraft\client\1.16.5-20210115.111550\client-1.16.5-20210115.111550-slim.jar
Some extra libraries are missing! Running the installer to generate them now.

Exception in thread "main"
java.lang.reflect.InvocationTargetException
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.base/java.lang.reflect.Method.invoke(Unknown Source)

        at io.github.zekerzhayard.forgewrapper.installer.Main.main(Main.java:50)
Caused by: java.lang.NoSuchMethodError: 'net.minecraftforge.installer.json.Install net.minecraftforge.installer.json.Util.loadInstallProfile()'
        at io.github.zekerzhayard.forgewrapper.installer.util.InstallerV0.loadInstallProfile(InstallerV0.java:14)
        at io.github.zekerzhayard.forgewrapper.installer.Installer.install(Installer.java:15)
        ... 5 more

[ZekerZhayard]