$ git clone -n https://src.fedoraproject.org/rpms/grepcidr.git /var/lib/mock/f45-build-13022-446/root/chroot_tmpdir/scmroot/grepcidr
Cloning into '/var/lib/mock/f45-build-13022-446/root/chroot_tmpdir/scmroot/grepcidr'...
$ git fetch origin 5f02660593d2c0d4b21710161004e71b745c488b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/grepcidr
 * [new ref]         5f02660593d2c0d4b21710161004e71b745c488b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5f02660 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild