$ git clone -n https://src.fedoraproject.org/rpms/rust-difftastic.git /var/lib/mock/f41-build-side-1-3133942-39708/root/chroot_tmpdir/scmroot/rust-difftastic
Cloning into '/var/lib/mock/f41-build-side-1-3133942-39708/root/chroot_tmpdir/scmroot/rust-difftastic'...
$ git fetch origin b2e69083122beeb414a2a8a5b1c15fe6f982c9f6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-difftastic
 * [new ref]         b2e69083122beeb414a2a8a5b1c15fe6f982c9f6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b2e6908 Update to version 0.61.0; Fixes: RHBZ#2321385