$ git clone -n https://src.fedoraproject.org/rpms/libgit2_1.6.git /var/lib/mock/f41-build-side-1-3057323-38399/root/chroot_tmpdir/scmroot/libgit2_1.6
Cloning into '/var/lib/mock/f41-build-side-1-3057323-38399/root/chroot_tmpdir/scmroot/libgit2_1.6'...
$ git fetch origin c5b57edf943eb196ce70aa4df7dd852342c9ea25:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libgit2_1.6
 * [new ref]         c5b57edf943eb196ce70aa4df7dd852342c9ea25 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c5b57ed Retire unused compat package