Merge pull request #68750 from tchaikov/wip-crimson-merge-coll

crimson/os: implement OP_MERGE_COLLECTION

Reviewed-by: Matan Breizman <mbreizma@redhat.com>
Reviewed-by: Xuehan Xu <xuxuehan@qianxin.com>

diff --cc src/test/crimson/seastore/test_seastore.cc
Simple merge