$ git clone -n https://src.fedoraproject.org/rpms/pdfmixtool.git /var/lib/mock/f45-build-21505-586/root/chroot_tmpdir/scmroot/pdfmixtool
Cloning into '/var/lib/mock/f45-build-21505-586/root/chroot_tmpdir/scmroot/pdfmixtool'...
$ git fetch origin 54f8a8437b206d1abb05c8507300b8af9788a4f3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/pdfmixtool
 * [new ref]         54f8a8437b206d1abb05c8507300b8af9788a4f3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 54f8a84 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild