Add support for custom module connection status

[nfmohit]

Feature Description

The Site Kit Settings -> Connected Services screen displays the module status if a module is connected or prompts to complete setup if the connection is incomplete.

We should add support for custom status, for example, when a module needs attention from the owner.

This is needed at the moment to support for adding a "Action needed" status for the Reader Revenue Manager module.

• Read more in the design doc.

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Acceptance criteria

Implementation Brief

Test Coverage

QA Brief

Changelog entry