Fix reporting exit code when command line export fails

Fixes godotengine#83042.

(cherry picked from commit 51bfda9)

editor/editor_node.cpp

@@ -993,7 +993,9 @@ void EditorNode::_fs_changed() {
 		if (err != OK) {
 			ERR_PRINT(export_error);
 			_exit_editor(EXIT_FAILURE);
-		} else if (!export_error.is_empty()) {
+			return;
+		}
+		if (!export_error.is_empty()) {
 			WARN_PRINT(export_error);
 		}
 		_exit_editor(EXIT_SUCCESS);