Add preprovision initializer for app platforms

[aapomm]

Summary

In App Platforms, assets:precompile is run before the DB is provisioned causing a ActiveRecord::ConnectionNotEstablished: connection to server at "127.0.0.1", port 5432 failed: Connection refused

Proposed Solution
Manually set the enabled_list to empty the specific use case

Testing Steps

Provide steps to test functionality, described in detail for someone not familiar with this part of the application / code base

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Check List

• Added a CHANGELOG entry
• Added specs