$ git clone -n https://src.fedoraproject.org/rpms/docker-buildx.git /var/lib/mock/f41-build-852282-166322/root/chroot_tmpdir/scmroot/docker-buildx
Cloning into '/var/lib/mock/f41-build-852282-166322/root/chroot_tmpdir/scmroot/docker-buildx'...
$ git fetch origin 5e451b58a4a872aac03437ef87a51ff9bd40011c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/docker-buildx
 * [new ref]         5e451b58a4a872aac03437ef87a51ff9bd40011c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5e451b5 Update to v0.17.0