mgr/dashboard: fix cephfs forms validations

mgr/dashboard: fix cephfs forms validations

1. CephFS Edit Form didnt had any validation for name eventhough the
   create had. So reused the Create form to display the Edit as well

2. Add Name Validations to Subvoume and Subvolume group forms

3. Removed the datePipe from the cephfs list template since we are using
   the relativeDate.

Fixes: https://tracker.ceph.com/issues/62939
Signed-off-by: Nizamudeen A <nia@redhat.com>