$ git clone -n https://src.fedoraproject.org/rpms/perl-Getopt-Yath.git /var/lib/mock/f45-build-23757-599/root/chroot_tmpdir/scmroot/perl-Getopt-Yath
Cloning into '/var/lib/mock/f45-build-23757-599/root/chroot_tmpdir/scmroot/perl-Getopt-Yath'...
$ git fetch origin 46a7f298e866faa5d431c65ab6091edeb1cdcef8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Getopt-Yath
 * [new ref]         46a7f298e866faa5d431c65ab6091edeb1cdcef8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 46a7f29 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild