[Fabric Studio] Network error when signing in to a deleted cluster

## Expected Behavior

Instead of Sign in form, display a message that the cluster has been deleted? We can look at the cluster data, if we have it, to see that it was terminated and won’t respond.

## Actual Behavior

'Network error' popup notification

## Steps to Reproduce

1. Go to an organization
2. Click View for a cluster
3. Copy the URL (i.e. )
4. Go back
5. Right click on the same cluster
6. Click Delete to delete the cluster
7. Access the above link directly
8. Enter the cluster credentials to sign in