selftests: mlxsw: spectrum-2: Remove q_in_vni_veto test

q_in_vni_veto.sh is not needed anymore because VxLAN with an 802.1ad
bridge and VxLAN with an 802.1d bridge can coexist.

Remove the test.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>