$ git clone -n https://src.fedoraproject.org/rpms/rust-iri-string.git /var/lib/mock/f45-build-42638-795/root/chroot_tmpdir/scmroot/rust-iri-string
Cloning into '/var/lib/mock/f45-build-42638-795/root/chroot_tmpdir/scmroot/rust-iri-string'...
$ git fetch origin 242ccbca051be723c9b00d0d99b8ca098a611998:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-iri-string
 * [new ref]         242ccbca051be723c9b00d0d99b8ca098a611998 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 242ccbc Update to version 0.7.14