$ git clone -n https://src.fedoraproject.org/rpms/squid.git /var/lib/mock/f38-build-side-42-init-devel-696597-27002/root/chroot_tmpdir/scmroot/squid
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-696597-27002/root/chroot_tmpdir/scmroot/squid'...
$ git fetch origin c4d9b668ca2a9caf3f357c3f7afd66af5061262c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/squid
 * [new ref]         c4d9b668ca2a9caf3f357c3f7afd66af5061262c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c4d9b66 new version 5.8