$ git clone -n https://src.fedoraproject.org/rpms/rubygem-net-http-persistent.git /var/lib/mock/f45-build-35050-693/root/chroot_tmpdir/scmroot/rubygem-net-http-persistent
Cloning into '/var/lib/mock/f45-build-35050-693/root/chroot_tmpdir/scmroot/rubygem-net-http-persistent'...
$ git fetch origin 956ca2fc6c96a4b4477f845d6189c6496c8dc5a8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-net-http-persistent
 * [new ref]         956ca2fc6c96a4b4477f845d6189c6496c8dc5a8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 956ca2f Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild