use neutron-lib for _model_query

The model_query module is in neutron-lib and the CommonDBMixin will
eventually be removed. This patch swiches use of the _model_query
method over to query_with_hooks from neutron-lib.

This patch also bumps the neutron-lib version up to 1.20.0

Change-Id: I8ff41c9d914b8329e4fca90de8a9ef9f41ccdcde

lower-constraints.txt

@@ -53,7 +53,7 @@ msgpack==0.5.6
 munch==2.2.0
 netaddr==0.7.19
 netifaces==0.10.6
-neutron-lib==1.18.0
+neutron-lib==1.20.0
 openstacksdk==0.12.0
 os-client-config==1.29.0
 os-service-types==1.2.0

neutron_taas/db/taas_db.py

@@ -21,6 +21,7 @@ from sqlalchemy.orm import exc
 from neutron.db import common_db_mixin as base_db
 from neutron_lib import constants
 from neutron_lib.db import model_base
+from neutron_lib.db import model_query
 from neutron_lib.plugins import directory
 from neutron_taas.extensions import taas
 from oslo_config import cfg
@@ -91,7 +92,7 @@ class Taas_db_Mixin(taas.TaasPluginBase, base_db.CommonDbMixin):
 
     def _get_tap_id_association(self, context, tap_service_id):
         try:
-            query = self._model_query(context, TapIdAssociation)
+            query = model_query.query_with_hooks(context, TapIdAssociation)
             return query.filter(TapIdAssociation.tap_service_id ==
                                 tap_service_id).one()
         except exc.NoResultFound:

requirements.txt

@@ -5,7 +5,7 @@
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
 Babel!=2.4.0,>=2.3.4 # BSD
 neutron>=12.0.0  # Apache-2.0
-neutron-lib>=1.18.0 # Apache-2.0
+neutron-lib>=1.20.0 # Apache-2.0
 
 # Opt-in for neutron-lib consumption patches
 # http://lists.openstack.org/pipermail/openstack-dev/2018-September/135063.html