$ git clone -n https://src.fedoraproject.org/rpms/rust-value-bag-serde1.git /var/lib/mock/f42-build-3251833-41222/root/chroot_tmpdir/scmroot/rust-value-bag-serde1
Cloning into '/var/lib/mock/f42-build-3251833-41222/root/chroot_tmpdir/scmroot/rust-value-bag-serde1'...
$ git fetch origin 14b6e54768404e43d1df37750407017ddecb8517:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-value-bag-serde1
 * [new ref]         14b6e54768404e43d1df37750407017ddecb8517 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 14b6e54 no longer needed