$ git clone -n https://src.fedoraproject.org/rpms/perl-Test-Warn.git /var/lib/mock/f45-build-26915-620/root/chroot_tmpdir/scmroot/perl-Test-Warn
Cloning into '/var/lib/mock/f45-build-26915-620/root/chroot_tmpdir/scmroot/perl-Test-Warn'...
$ git fetch origin f1ff10c327da109a865fdd08fdc6e660fefdc783:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Test-Warn
 * [new ref]         f1ff10c327da109a865fdd08fdc6e660fefdc783 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f1ff10c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild