GDScript: Fix type resolution not being return in some cases

Some situations caused the parser node type to not being update when
trying to resolve the type, returning invalid data and breaking the
parsing when it shouldn't. This patch fix the behavior.

(cherry picked from commit 64d09b7de532b75038c24e689d16a48a36678654)

modules/gdscript/gdscript_parser.cpp

@@ -6518,7 +6518,8 @@ GDScriptParser::DataType GDScriptParser::_reduce_node_type(Node *p_node) {
 		default: {}
 	}
 
-	p_node->set_datatype(_resolve_type(node_type, p_node->line));
+	node_type = _resolve_type(node_type, p_node->line);
+	p_node->set_datatype(node_type);
 	return node_type;
 }