Make visual effects serializable

[Romitou]

Description

Started by @TPGamesNL in PR #4123 (the commit has been cherry-picked and the author has been kept for credits), providing a serializer for VisualEffectType allows to serialize VisualEffect correctly. In fact, this should have been handled by simpleClassLoaders, where this specific class was originally registered.

However, the Yggdrasil#getSerializer method did not return a serializer: a SimpleClassResolver extends from ClassResolver and not from a YggdrasilSerializer like the others. A fix is therefore to directly register this serializer at the root of classResolvers.

https://github.com/SkriptLang/Skript/blob/master/src/main/java/ch/njol/yggdrasil/Yggdrasil.java

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Target Minecraft Versions: any Requirements: none Related Issues: #4196