rgw/lc: LCOpAction_CurrentExpiration checks mtime for delete markers

rgw/lc: LCOpAction_CurrentExpiration checks mtime for delete markers

the unconditional 'return true' for delete markers was causing check()
to ignore the lifecycle policy's "Days" field, causing delete markers to
be expired and removed prematurely

instead of the early return, fall through to the mtime/size comparisons
used for normal objects

Fixes: https://tracker.ceph.com/issues/73240
Signed-off-by: Casey Bodley <cbodley@redhat.com>
(cherry picked from commit 102eaa833d2b0c89a95a0e06876a16b3e2e6c6d8)