$ git clone -n https://src.fedoraproject.org/rpms/perl-Package-Generator.git /var/lib/mock/f40-build-2019857-46568/root/chroot_tmpdir/scmroot/perl-Package-Generator
Cloning into '/var/lib/mock/f40-build-2019857-46568/root/chroot_tmpdir/scmroot/perl-Package-Generator'...
$ git fetch origin a78bc8cbe993c35ace83da3d5533f7f0ebb2dfb4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Package-Generator
 * [new ref]         a78bc8cbe993c35ace83da3d5533f7f0ebb2dfb4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a78bc8c Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild