Consider SymbolFlags.Method as function-esque during js declaration emit

[weswigham]

The binder binds both "instance methods" and "static methods" of js class-like functions with SymbolFlags.Method. For instance methods, we recover them while emitting instance members, however for static methods, we rely on serializing the static side as a namespace augmentation on the class; so in those cases, we need to emit the method as a function instead.

Fixes #36270