$ git clone -n https://src.fedoraproject.org/rpms/obs-build.git /var/lib/mock/f39-build-2237121-53534/root/chroot_tmpdir/scmroot/obs-build
Cloning into '/var/lib/mock/f39-build-2237121-53534/root/chroot_tmpdir/scmroot/obs-build'...
$ git fetch origin dc1a09a94c1e16529ab8efebba17660bd9496a9d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/obs-build
 * [new ref]         dc1a09a94c1e16529ab8efebba17660bd9496a9d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dc1a09a New upstream release 20240111, fixes rhbz#2257997