cephfs,mon: require confirmation to fail unhealthy MDS

cephfs,mon: require confirmation to fail unhealthy MDS

When running the command "ceph mds fail" for an MDS that is unhealthy
due to, MDS_CACHE_OVERSIZED or MDS_TRIM, user must pass confirmation
flag. Else, the command will fail and print an appropriate error
message.

Restarting an MDS with such health warnings is not recommended since it
will have a slow reocvery during restart which will create new problems.

Fixes: https://tracker.ceph.com/issues/61866
Signed-off-by: Rishabh Dave <ridave@redhat.com>