IJPL-192625 We should not call YouTrack on every start if users has not valid credentials

GitOrigin-RevId: 2c5e56d807d343c788a918ce8b80e9ec9717b52f

plugins/tasks/tasks-core/src/com/intellij/tasks/youtrack/YouTrackRepository.java

@@ -110,6 +110,11 @@ public class YouTrackRepository extends NewBaseRepositoryImpl {
     }
   }
 
+  @Override
+  public boolean isConfigured() {
+    return super.isConfigured() && StringUtil.isNotEmpty(getUsername());
+  }
+
   @Override
   public @Nullable CancellableConnection createCancellableConnection() {
     return new HttpTestConnection(new HttpGet()) {