$ git clone -n https://src.fedoraproject.org/rpms/lxlauncher.git /var/lib/mock/f42-build-side-1-3499834-45966/root/chroot_tmpdir/scmroot/lxlauncher
Cloning into '/var/lib/mock/f42-build-side-1-3499834-45966/root/chroot_tmpdir/scmroot/lxlauncher'...
$ git fetch origin 3af7756f93958dcd00a8de5aaa74ee6d5b15d92c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/lxlauncher
 * [new ref]         3af7756f93958dcd00a8de5aaa74ee6d5b15d92c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3af7756 add git for BR