$ git clone -n https://src.fedoraproject.org/rpms/ghc-x509-system.git /var/lib/mock/f41-build-side-1-3126842-39527/root/chroot_tmpdir/scmroot/ghc-x509-system
Cloning into '/var/lib/mock/f41-build-side-1-3126842-39527/root/chroot_tmpdir/scmroot/ghc-x509-system'...
$ git fetch origin 88c6d0c7d85c4b72781a35d6b43cf29dfa23b841:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-x509-system
 * [new ref]         88c6d0c7d85c4b72781a35d6b43cf29dfa23b841 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 88c6d0c Replaced by ghc-crypton-x509-system