Use new method in check to prevent removal of last KRA
It previously used a vault connection to determine if any
KRA servers were installed. This would fail if the last KRA
was not available.
Use server roles instead to determine if the last KRA server
is to be removed.
https://pagure.io/freeipa/issue/8397
Signed-off-by: Rob Crittenden <rcritten@redhat.com>
Reviewed-By: Francois Cami <fcami@redhat.com>