$ git clone -n https://src.fedoraproject.org/rpms/rust-twox-hash.git /var/lib/mock/f45-build-45836-828/root/chroot_tmpdir/scmroot/rust-twox-hash
Cloning into '/var/lib/mock/f45-build-45836-828/root/chroot_tmpdir/scmroot/rust-twox-hash'...
$ git fetch origin 9e22f540159a21fb31b4a96ba65f01e6f7d424c4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-twox-hash
 * [new ref]         9e22f540159a21fb31b4a96ba65f01e6f7d424c4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9e22f54 Update to version 2.1.4; Fixes RHBZ#2524962