$ git clone -n https://src.fedoraproject.org/rpms/R-timeDate.git /var/lib/mock/f45-build-6465-348/root/chroot_tmpdir/scmroot/R-timeDate
Cloning into '/var/lib/mock/f45-build-6465-348/root/chroot_tmpdir/scmroot/R-timeDate'...
$ git fetch origin 21146fb9d8a81f38082f0f347a6c6ec139ad8813:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-timeDate
 * [new ref]         21146fb9d8a81f38082f0f347a6c6ec139ad8813 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 21146fb Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild