XDCR setup screens missing spinner

With half-mode encryption, XDCR still need to make a call to remote cluster, which could take a while or could experience timeouts if the remote cluster doesn't have the port opened up.

This is the case where we experienced when contacting couchbase cloud, which has 8091 blocked off.

With half-encryption mode, there is no spinner showing up like it does with full encryption mode - and user is left hanging what is happening before XDCR returns an error code.

Please see attached video

Edit: Note that it seems that full-encryption mode spinner is also gone too

Edit (9/4) - the spinner should show for both adding a remote cluster and adding a replication... since when using it against a cluster that's far away where latency is an issue, both situations could take a few seconds and a spinner would be helpful