Updated nextcloud neon api to latest

lib/view/pages/files/files.dart

@@ -189,7 +189,7 @@ class _FilesState extends State<Files> {
                           }, child: const Text("Abbrechen")),
                           TextButton(onPressed: () {
                             WebdavApi.webdav.then((webdav) {
-                              webdav.mkdirs("${widget.path.join("/")}/${inputController.text}").then((value) => _query());
+                              webdav.mkcol("${widget.path.join("/")}/${inputController.text}").then((value) => _query());
                             });
                             Navigator.of(context).pop();
                           }, child: const Text("Ordner erstellen")),