$ git clone -n https://src.fedoraproject.org/rpms/ghc-Diff.git /var/lib/mock/f45-build-9879-411/root/chroot_tmpdir/scmroot/ghc-Diff
Cloning into '/var/lib/mock/f45-build-9879-411/root/chroot_tmpdir/scmroot/ghc-Diff'...
$ git fetch origin 5fd90177808213559a0a1eb49ebc29ce48f1954a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-Diff
 * [new ref]         5fd90177808213559a0a1eb49ebc29ce48f1954a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5fd9017 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild