After enabling FDW, FDW tables were not automatically refreshed

Summary

A customer had upgraded to 10.7 and FDW was not working because the tables were not refreshed.

Steps to reproduce

This is an attempt to summarize what happened leading up the issue.

Before the issue:

• Setup GitLab 10.5.4 with Geo
• On the secondary, have an external Postgres server for the main db, and another server for the tracking DB
• Disable auto_migrate
• Upgrade to 10.7
• In /admin/geo_nodes, see a warning about FDW not being enabled

And then the issue:

• Enable FDW as in https://docs.gitlab.com/ee/administration/geo/replication/database.html#tracking-database-for-the-secondary-nodes
• The FDW tables should be refreshed automatically, but weren't, so everything still says FDW is disabled

What is the current bug behavior?

FDW tables needed to be refreshed, but weren't automatically.

What is the expected correct behavior?

FDW tables are refreshed automatically if they need to be.

Customer ticket (internal only)

Workaround

https://docs.gitlab.com/ee/administration/geo/replication/troubleshooting.html#geo-database-has-an-outdated-fdw-remote-schema-error