Support tags for Octavia pool member

The API doc:
https://developer.openstack.org/api-ref/load-balancer/v2/index.html#create-member

Change-Id: I6c5aaf116916eb197a62d89561d4d20236006581
Story: #2005219
Task: #29998

heat/engine/resources/openstack/octavia/pool_member.py

@@ -15,6 +15,7 @@ from heat.common.i18n import _
 from heat.engine import constraints
 from heat.engine import properties
 from heat.engine.resources.openstack.octavia import octavia_base
+from heat.engine import support
 from heat.engine import translation
 
 
@@ -26,10 +27,10 @@ class PoolMember(octavia_base.OctaviaBase):
 
     PROPERTIES = (
         POOL, ADDRESS, PROTOCOL_PORT, MONITOR_ADDRESS, MONITOR_PORT,
-        WEIGHT, ADMIN_STATE_UP, SUBNET,
+        WEIGHT, ADMIN_STATE_UP, SUBNET, TAGS
     ) = (
         'pool', 'address', 'protocol_port', 'monitor_address', 'monitor_port',
-        'weight', 'admin_state_up', 'subnet'
+        'weight', 'admin_state_up', 'subnet', 'tags'
     )
 
     ATTRIBUTES = (
@@ -101,6 +102,13 @@ class PoolMember(octavia_base.OctaviaBase):
                 constraints.CustomConstraint('neutron.subnet')
             ],
         ),
+        TAGS: properties.Schema(
+            properties.Schema.LIST,
+            _('A list of simple strings assigned to the member. The property '
+              'is supported with Stein Octavia or newer version.'),
+            update_allowed=True,
+            support_status=support.SupportStatus(version='13.0.0'),
+        ),
     }
 
     def translation_rules(self, props):

heat/tests/openstack/octavia/inline_templates.py

@@ -80,6 +80,7 @@ resources:
       weight: 1
       subnet: sub123
       admin_state_up: True
+      tags: ['tag1', 'tag2']
 '''
 
 MONITOR_TEMPLATE = '''

heat/tests/openstack/octavia/test_pool_member.py

@@ -61,6 +61,7 @@ class PoolMemberTest(common.HeatTestCase):
                 'weight': 1,
                 'subnet_id': '123',
                 'admin_state_up': True,
+                'tags': ['tag1', 'tag2']
             }
         }
         props = self.member.handle_create()
@@ -95,6 +96,7 @@ class PoolMemberTest(common.HeatTestCase):
         prop_diff = {
             'admin_state_up': False,
             'weight': 2,
+            'tags': ['tag3', 'tag4']
         }
 
         prop_diff = self.member.handle_update(None, None, prop_diff)

releasenotes/notes/octavia-member-tags-84cd00224d6b7bc1.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - Support ``tags`` property for the resource ``OS::Octavia::PoolMember``, the
+    property is allowed to be updated as well. The resource tag was introduced
+    in Octavia since Stein release, do not specify tags in Heat template if you are
+    using the previous versions.