Follow up to change of exception raised

The patch in the Depends-On line changed the class of an exception
raised in neutron-lib. This change adapts neutron code where we expected
the exception changed.

Change-Id: I34f7d2aab0af0b985d9165465fe9e7c656041745
Depends-On: https://review.opendev.org/695205

neutron/services/segments/plugin.py

@@ -224,7 +224,7 @@ class NovaSegmentNotifier(object):
                 self.p_client.update_resource_provider_inventory(
                     event.segment_id, ipv4_inventory, IPV4_RESOURCE_CLASS)
                 return
-            except placement_exc.PlacementInventoryUpdateConflict:
+            except placement_exc.PlacementResourceProviderGenerationConflict:
                 LOG.debug('Re-trying to update Nova IPv4 inventory for '
                           'routed network segment: %s', event.segment_id)
         LOG.error('Failed to update Nova IPv4 inventory for routed '

neutron/tests/unit/extensions/test_segment.py

@@ -2258,9 +2258,9 @@ class TestNovaSegmentNotifier(SegmentAwareIpamTestCase):
                 self.mock_p_client.get_inventory.return_value = inventory
                 self.mock_p_client.update_resource_provider_inventory.\
                     side_effect = (
-                        placement_exc.PlacementInventoryUpdateConflict(
-                            resource_provider=mock.ANY,
-                            resource_class=seg_plugin.IPV4_RESOURCE_CLASS))
+                        placement_exc.
+                        PlacementResourceProviderGenerationConflict(
+                            resource_provider=mock.ANY, generation=1))
                 self.segments_plugin.nova_updater._update_nova_inventory(event)
                 self.assertEqual(seg_plugin.MAX_INVENTORY_UPDATE_RETRIES,
                                  self.mock_p_client.get_inventory.call_count)