tests: enable test_get_objects_queries_constant for trunk ports
tests: enable test_get_objects_queries_constant for trunk ports

Now that trunk model has a relationship for sub ports [1], this test can
be enabled.

[1] I1678301734e7f945e6f0400e62970b908da77a71

Partially-Implements: bp/adopt-oslo-versioned-objects-for-db
Change-Id: I9406732427ba3386b86a108fd687c2a057b1a4b3

eayunstack/neutron,cloudbase/neutron,mahak/neutron,cloudbase/neutron,sebrandon1/neutron,igor-toga/local-snat,huntxu/neutron,igor-toga/local-snat,eayunstack/neutron,openstack/neutron,mahak/neutron,openstack/neutron,mahak/neutron,openstack/neutron,sebrandon1/neutron,noironetworks/neutron,huntxu/neutron,noironetworks/neutron