The failover of the arbiter mon in a stretch cluster was sometimes
failing due to the new tiebreaker not being set in ceph.
Rook would repeatedly try to remove the old tiebreaker mon
and keep failing because the new tiebreaker had not been set.
Now we make setting the tiebreaker idempotent in case the operator
restarts in the middle of the operation or some other corner
case causes the expected tiebreaker to be set. In that case,
the next reconcile will also ensure the tiebreaker mon is
set as expected.
Signed-off-by: Travis Nielsen <tnielsen@redhat.com>