$ git clone -n https://src.fedoraproject.org/rpms/rust-siphasher.git /var/lib/mock/f39-build-1517176-35695/root/chroot_tmpdir/scmroot/rust-siphasher
Cloning into '/var/lib/mock/f39-build-1517176-35695/root/chroot_tmpdir/scmroot/rust-siphasher'...
$ git fetch origin c9ad99283de104fddc91e19bd8943f491337585b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-siphasher
 * [new ref]         c9ad99283de104fddc91e19bd8943f491337585b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c9ad992 Regenerate with rust2rpm v24