$ git clone -n https://src.fedoraproject.org/rpms/ghc-req.git /var/lib/mock/f41-build-side-1-2883180-34500/root/chroot_tmpdir/scmroot/ghc-req
Cloning into '/var/lib/mock/f41-build-side-1-2883180-34500/root/chroot_tmpdir/scmroot/ghc-req'...
$ git fetch origin 2da4b4b5b1e2952f2ddf673f8f4274384125e4ed:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-req
 * [new ref]         2da4b4b5b1e2952f2ddf673f8f4274384125e4ed -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2da4b4b https://hackage.haskell.org/package/req-3.13.2/changelog