ctdb-recoverd: Do not ban on unknown error when taking cluster lock
If the cluster filesystem is unavailable then I/O errors may occur.
This is no worse than contention, so don't ban. This avoids having
services unavailable for longer than necessary.
Update the associated test to simply confirm that this results in a
leaderless cluster, and leadership is restored when the lock can once
again be taken.
Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>