doc/radosgw: Remove stale versionadded directives for EOL releases

Every feature marked with .. versionadded:: Jewel, Kraken, Luminous,
Mimic, or Nautilus has been present in Ceph for between 5 and 9 years.
These directives add visual noise without informing users, since all
currently supported releases already include these features.

Remove versionadded directives for these five EOL releases from 20
radosgw .rst files (48 lines removed). Directives for Octopus and
later are retained.

Fixes: https://tracker.ceph.com/issues/77194

Signed-off-by: Emmanuel Ameh <eameh@contractor.linuxfoundation.org>