rgw: return OK on consecutive complete-multipart reqs

rgw: return OK on consecutive complete-multipart reqs

Fixes: https://tracker.ceph.com/issues/50141
Signed-off-by: Mark Kogan <mkogan@redhat.com>
fixup! rgw: return OK on consecutive complete-multipart reqs

(cherry picked from commit 324c377849a5d246f689f6e7a2862f42f1504d2c)

Conflicts: src/rgw/rgw_op.h src/rgw/rgw_op.cc

Cherry-pick notes:
- Conflicts due in rgw_op.h due to execute method adjacent to change not having optional_yield arg
- Conflicts in rgw_op.cc due to lack of rgw::sal::Object encapsulation in Octopus