$ git clone -n https://src.fedoraproject.org/rpms/perl-Shell.git /var/lib/mock/f45-build-26241-616/root/chroot_tmpdir/scmroot/perl-Shell
Cloning into '/var/lib/mock/f45-build-26241-616/root/chroot_tmpdir/scmroot/perl-Shell'...
$ git fetch origin 4a282b0e7c9ba328ff0e55482671b3d9cbcf6f1b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Shell
 * [new ref]         4a282b0e7c9ba328ff0e55482671b3d9cbcf6f1b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4a282b0 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild