Method is_vararg

modules/gdscript/gdscript_function.h:605–605

	_FORCE_INLINE_ GDScript *get_script() const { return _script; }
	_FORCE_INLINE_ bool is_static() const { return _static; }
	_FORCE_INLINE_ bool is_vararg() const { return _vararg_index >= 0; }
	_FORCE_INLINE_ MethodInfo get_method_info() const { return method_info; }
	_FORCE_INLINE_ int get_argument_count() const { return _argument_count; }
	_FORCE_INLINE_ Variant get_rpc_config() const { return rpc_config; }