$ git clone -n https://src.fedoraproject.org/rpms/krfb.git /var/lib/mock/f39-build-1766809-41501/root/chroot_tmpdir/scmroot/krfb
Cloning into '/var/lib/mock/f39-build-1766809-41501/root/chroot_tmpdir/scmroot/krfb'...
$ git fetch origin c9218606a3943bbc1f669d01c5e3b29011b41de7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/krfb
 * [new ref]         c9218606a3943bbc1f669d01c5e3b29011b41de7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c921860 23.08.3