Add Alerta_password before the starting MCP update process

PROD-35843

Change-Id: Ia133ad285c8f46ed176ce72cc8f8e870d201117d
diff --git a/tcp_tests/tests/system/test_mcp_update.py b/tcp_tests/tests/system/test_mcp_update.py
index d1b30ea..5d06b63 100644
--- a/tcp_tests/tests/system/test_mcp_update.py
+++ b/tcp_tests/tests/system/test_mcp_update.py
@@ -110,6 +110,25 @@
         "I@galera:master or I@galera:slave", "haproxy")
 
 
+@pytest.fixture
+def wa_for_alerta_password_prod35958(reclass_actions,
+                                     salt_actions):
+    reclass_actions.add_key(
+        "parameters._param.alerta_admin_api_key_generated",
+        "a"*32,
+        "cluster/*/infra/secrets.yml")
+    salt_actions.run_state(
+        "I@prometheus:alerta or I@prometheus:alertmanager",
+        "saltutil.refresh_pillar")
+    salt_actions.enforce_state(
+        "I@prometheus:alerta", "prometheus.alerta")
+    salt_actions.enforce_state(
+        "I@prometheus:alertmanager", "prometheus.alertmanager")
+    salt_actions.enforce_state(
+        "I@prometheus:alerta or I@prometheus:alertmanager",
+        "docker.client")
+
+
 @pytest.fixture(scope='class')
 def enable_openstack_update(reclass_actions, salt_actions):
     param = "parameters._param.openstack_upgrade_enabled"
@@ -125,7 +144,8 @@
 
 
 @pytest.mark.usefixtures("switch_to_proposed_pipelines",
-                         "wa_for_galera_clustercheck_password_prod35705")
+                         "wa_for_galera_clustercheck_password_prod35705",
+                         "wa_for_alerta_password_prod35958")
 class TestUpdateMcpCluster(object):
     """
     Following the steps in