No option to reset sharing permissions or recover a module if owner no longer exists

Bug Description

When performing some Dashboard Sharing checks, I ran into an issue whereby if one administrator who the module owner no longer exists, module recovery no longer occurs. This occurred when the Google account associated with module owner (which was a secondary administrator user) may have been used at some stage as the primary user (ie. The primary user/Site Kit owner, was changed by disconnecting and connecting once more).

Further testing ongoing, with steps to reproduce to be added.

Steps to reproduce

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Screenshots

Additional Context

• SK 1.139.0
• Potential bug, discovered during testing related to a support topic
• UPDATE: Reset sharing permissions does appear if you apply DS sharing options for other modules. This however, can't be used as a workaround as resetting will only reset modules owner by the user resetting.

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Acceptance criteria

Implementation Brief

Test Coverage

QA Brief

Changelog entry

Start by reproducing the problem through the Dashboard Sharing checks described in the issue, using the reported Site Kit 1.139.0 setup with a deleted module owner. Trace the module recovery and reset-sharing-permissions paths; done means recovery works when the owner no longer exists and the behavior is covered by reproducible steps and tests.