$ git clone -n https://src.fedoraproject.org/rpms/ghc-unix-time.git /var/lib/mock/f41-build-839095-159992/root/chroot_tmpdir/scmroot/ghc-unix-time
Cloning into '/var/lib/mock/f41-build-839095-159992/root/chroot_tmpdir/scmroot/ghc-unix-time'...
$ git fetch origin a85afd68c7c65288ef06353c83cc1e323c117c52:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-unix-time
 * [new ref]         a85afd68c7c65288ef06353c83cc1e323c117c52 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a85afd6 https://hackage.haskell.org/package/unix-time-0.4.15/changelog