Add new GDScript type checker

modules/gdscript/gdscript_parser.cpp

@@ -1894,6 +1894,8 @@ GDScriptParser::ExpressionNode *GDScriptParser::parse_await(ExpressionNode *p_pr
 	AwaitNode *await = alloc_node<AwaitNode>();
 	await->to_await = parse_precedence(PREC_AWAIT, false);
 
+	current_function->is_coroutine = true;
+
 	return await;
 }