Comment 2 for bug 1737779

I'm adding Cinder to this bug report since this is arguably a bug in the PUT /attachments/{id} API since the connector dict is per compute host, so shoving the mountpoint down in the host connector dict is confusing and wrong IMO - the mountpoint is per volume attachment, so it should be a top-level field on the volume attachment itself.

Making that change to the PUT /attachments/{id} request format would be a microversion change though so I'm just documenting it here for a future enhancement.