Update Player CharacterAppearanceLoaded

[Specifix5]

When using custom character implementations such as using a StarterCharacter, people should handle the character appearance themselves. This serves as a note, a warning that CharacterAppearanceLoaded does not fire for custom characters.

Changes

Added an additional note for when this event (CharacterAppearanceLoaded) should not be used (such as using StarterCharacters), because it will not fire and I think this note will save a lot of people from headache debugging.

      For custom character implementations, such as using a `Class.StarterPlayer|StarterCharacter`,
      Use `Class.Player.CharacterAdded` and handle your own accessories.

Reference:
https://devforum.roblox.com/t/playercharacterappearanceloaded-does-not-fire-if-there-is-a-startercharacter-present/3684116

Checks

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[github-actions]

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