fix: set node to null if not in intranet

@@ -108,6 +108,7 @@ export class Repository {
                     console.log("prepare local couch url: ", localCouchUrl);
                     resolve(this.prepare(localCouchUrl));
                 }).catch(() => {
+                    this._node = null;
                     resolve(this.prepare(response.db_url));
                 });
         });