$ git clone -n https://src.fedoraproject.org/rpms/perl-Chemistry-Mol.git /var/lib/mock/f45-build-22280-590/root/chroot_tmpdir/scmroot/perl-Chemistry-Mol
Cloning into '/var/lib/mock/f45-build-22280-590/root/chroot_tmpdir/scmroot/perl-Chemistry-Mol'...
$ git fetch origin 9f5424145dcf47a9cce8a9ddde27a59767bf2057:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Chemistry-Mol
 * [new ref]         9f5424145dcf47a9cce8a9ddde27a59767bf2057 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9f54241 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild