'sha_attribute' causes error when Geo is not enabled

What does this MR do?

Adds a new parameter to sha_attribute to indicate whether the database is available or not. This allows us to pass in ::Gitlab::Geo.geo_database_configured? so that sha_attribute will not check for table existence if the Geo database is not configured.

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

An EE installation was still eager loading the geo models, which used the sha_attribute and tried to check the existence of the Geo db.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• [-] Changelog entry added, if necessary
• [-] Documentation created/updated
• [-] API support added
• [-] Tests added for this feature/bug
• Review
  • [-] Has been reviewed by UX
  • [-] Has been reviewed by Frontend
  • Has been reviewed by Backend
  • [-] Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• [-] Internationalization required/considered
• [-] If paid feature, have we considered GitLab.com plan and how it works for groups and is there a design for promoting it to users who aren't on the correct plan
• End-to-end tests pass (package-qa manual pipeline job)

What are the relevant issue numbers?

https://gitlab.com/gitlab-org/gitlab-ee/issues/5587