$ git clone -n https://src.fedoraproject.org/rpms/usd.git /var/lib/mock/f41-build-808146-145693/root/chroot_tmpdir/scmroot/usd
Cloning into '/var/lib/mock/f41-build-808146-145693/root/chroot_tmpdir/scmroot/usd'...
$ git fetch origin 470014a4cc17db4144957a4dc142361fbd5191c1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/usd
 * [new ref]         470014a4cc17db4144957a4dc142361fbd5191c1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 470014a Update usd.spec