$ git clone -n https://src.fedoraproject.org/rpms/rust-git-delta.git /var/lib/mock/f38-build-side-43-rust-devel-1421761-31465/root/chroot_tmpdir/scmroot/rust-git-delta
Cloning into '/var/lib/mock/f38-build-side-43-rust-devel-1421761-31465/root/chroot_tmpdir/scmroot/rust-git-delta'...
$ git fetch origin 20b9c9598e902a1c7bd7fa4f15d105ace627f00d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-git-delta
 * [new ref]         20b9c9598e902a1c7bd7fa4f15d105ace627f00d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 20b9c95 Rebuilt for vte 0.11