$ git clone -n https://src.fedoraproject.org/rpms/tagtool.git /var/lib/mock/f41-build-1041904-18994/root/chroot_tmpdir/scmroot/tagtool
Cloning into '/var/lib/mock/f41-build-1041904-18994/root/chroot_tmpdir/scmroot/tagtool'...
$ git fetch origin 585ed056225aefba33d3db5b4dec6faa78659cd4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tagtool
 * [new ref]         585ed056225aefba33d3db5b4dec6faa78659cd4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 585ed05 Eliminate use of obsolete %patchN syntax (#2283636)