Currently, when importing a repository and the import fails due to authentication (wrong/invalid/missing credentials), the following error message is shown :

Git clone failed: <class 'bitbucket.apps.asyncx.tasks.RepoImportTask.ImportException'>: Command failed. Return value: 128

As error doesn't bring much details of what caused the issue, it may confuse the users on troubleshooting and fixing it.

This feature request is to improve the error message when the import fails due to authentication error, so it's more clear to the user what caused the issue leading them to double-check the credentials and potentially avoid the need of opening a support case.