$ git clone -n https://src.fedoraproject.org/rpms/rust-ptyprocess.git /var/lib/mock/f41-build-side-1-3134894-39763/root/chroot_tmpdir/scmroot/rust-ptyprocess
Cloning into '/var/lib/mock/f41-build-side-1-3134894-39763/root/chroot_tmpdir/scmroot/rust-ptyprocess'...
$ git fetch origin ee993d1ca1be68a312c3f5d5f5253d1c1102ad19:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-ptyprocess
 * [new ref]         ee993d1ca1be68a312c3f5d5f5253d1c1102ad19 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ee993d1 no longer needed