Run database migrate for horizon during upgrade

Change-Id: I1db585242cc3a5dcb2fe1ac79091d19f624c6f70
Closes-Bug: #1758855

ansible/roles/horizon/tasks/upgrade.yml

 ---
-- include: deploy.yml
+- include: config.yml
+
+- include: clone.yml
+  when:
+    - horizon_dev_mode | bool
+
+- include: bootstrap_service.yml
+  when: horizon_backend_database | bool
+
+- name: Flush handlers
+  meta: flush_handlers