[BUG] Function arguments can persist in other functions

[NotHyper-474]

This code snippet should be enough. Apparently this has been a bug for a very long time, considering Nene's script's moveByNoteKind seems to accidentally make use of it since, despite having a "kind" argument, it's using onNoteHit's "event" argument instead.

import funkin.modding.module.Module;

class Issue346 extends Module
{
	public function new()
	{
		super('IssueBug');
	}

	override function onCreate(event)
	{
		someFunc();
	}

	function someFunc():Void
	{
		// Traces event even though it should only exist in the function that called it.
		trace(event);
	}
}