BS 1.29.4/1.30 - Unity upgrade

[ErisApps]

This PR tracks the changes needed for the new BS version with the upgraded underlying Unity version.

• Fixes reference to Tweening-related code
• ~Changed TFM from net472 to netstandard2.1~ Shelved indefinitely due to https://github.com/dotnet/standard/issues/1662
• Removed obsolete Converter logic
• More code cleanup
• Switched to BepInEx.AssemblyPublicizer due to removal of BSIPA's virtualizer.
• Bumped dependencies