Require l3-ha extension for test_centralized_router_update_to_dvr
Require l3-ha extension for test_centralized_router_update_to_dvr

Since Ib262f32133aae50cdb01d2489830499fb5c30f44, the test explicitly
passes ha=False argument when creating a centralized router. This
attribute belongs to l3-ha API extension, and may be not present for
some neutron setups (f.e. when using networking-odl).

Skip the test if the extension is not enabled.

Change-Id: I71059bb2fd8c13270b7a9c3f0a6a07de310b26fc

Juniper/tempest,Tesora/tesora-tempest,vedujoshi/tempest,Juniper/tempest,masayukig/tempest,vedujoshi/tempest,Tesora/tesora-tempest,cisco-openstack/tempest,openstack/tempest,cisco-openstack/tempest,masayukig/tempest,openstack/tempest