$ git clone -n https://src.fedoraproject.org/rpms/python-blinker.git /var/lib/mock/f45-build-29784-641/root/chroot_tmpdir/scmroot/python-blinker
Cloning into '/var/lib/mock/f45-build-29784-641/root/chroot_tmpdir/scmroot/python-blinker'...
$ git fetch origin c6838aa50acf766b77f7415febbeec2edf35e139:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-blinker
 * [new ref]         c6838aa50acf766b77f7415febbeec2edf35e139 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c6838aa Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild