$ git clone -n https://src.fedoraproject.org/rpms/bomber.git /var/lib/mock/f39-build-1871417-42706/root/chroot_tmpdir/scmroot/bomber
Cloning into '/var/lib/mock/f39-build-1871417-42706/root/chroot_tmpdir/scmroot/bomber'...
$ git fetch origin c75a3d23306b1ac6c97085718450c2cc4e333083:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/bomber
 * [new ref]         c75a3d23306b1ac6c97085718450c2cc4e333083 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c75a3d2 23.08.3