[UT] "test_negative_update_floatingip_port_forwarding" does not create the ports in the correct subnet

[Rodolfo Alonso]

The ``NeutronDbPluginV2TestCase.port`` method input parameters are misleading. The "subnet" parameter won't create a port in the subnet selected; the method will extract the network and will enforce only the creation of the port on this network.

In order to create a port on the required subnet, the parameter "fixed_ips" should be provided instead.

The test ``test_negative_update_floatingip_port_forwarding`` is failing in [1].

[1]https://438434f768f3cb6b0f33-325b4a96905c9937625b58a50d186e45.ssl.cf2.rackcdn.com/887270/1/gate/cross-neutron-py310/e22eb16/testr_results.html

[Rodolfo Alonso (rodolfo-alonso-hernandez)]

Patch: https://review.opendev.org/c/openstack/neutron/+/887495

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 23.0.0.0b3 development milestone.