[Bug Report] Eval commands don't work

[hermitoff]

Bug Description

Hi When an eval command is used the bot doesn't reply and make an error in the console.

(No reply from the bot)

Steps to Reproduce

1. Use an eval command (like @bot eval jda.guilds)
2. See the console
3. White this..

Expected Result

Just execute the command and reply

Debug Output

System Properties:
  java.version = 16.0.2
  java.vm.name = Java HotSpot(TM) 64-Bit Server VM
  java.vm.specification.version = 16
  java.runtime.name = Java(TM) SE Runtime Environment
  java.runtime.version = 16.0.2+7-67
  java.specification.version = 16
  os.arch = x86_64
  os.name = Mac OS X

JMusicBot Information:
  Version = 0.3.5
  Owner = 572651719109115904
  Prefix = ;
  AltPrefix = @mention
  MaxSeconds = 0
  NPImages = false
  SongInStatus = false
  StayInChannel = false
  UseEval = true
  UpdateAlerts = true

Dependency Information:
  JDA Version = 4.3.0_312
  JDA-Utilities Version = 3.0.5
  Lavaplayer Version = 1.3.78

Runtime Information:
  Total Memory = 45
  Used Memory = 33

Discord Information:
  ID = 776019442538643476
  Guilds = 5
  Users = 3

### Additional Info

none

### Checklist

- [X] I have looked for information about this [within the documentation](https://jmusicbot.com/)
- [X] I have searched for similar issues [on the issues page](https://github.com/jagrosh/MusicBot/issues?q=is%3Aissue)
- [X] I am running the latest version of the bot: ![Release](https://img.shields.io/github/release/jagrosh/MusicBot.svg)

[MichailiK]

The eval command no longer works starting Java 14 (i think?) & above.