Adds migration step from nova to nova_api database

This patch adds a missing required step to migrate information from the nova
to the new nova_api database.

Closes-Bug: #1565497

Change-Id: Ia1554e12c688e5a6509af2d37f1825fd4ab666be
Co-Authored-By: Steven Dake <stdake@cisco.com>

docker/nova/nova-api/extend_start.sh

@@ -5,5 +5,6 @@
 if [[ "${!KOLLA_BOOTSTRAP[@]}" ]]; then
     nova-manage db sync
     nova-manage api_db sync
+    nova-manage db online_data_migrations
     exit 0
 fi