Remove the credential reuse code

[dkotter]

Description of the Change

In order to simplify #1038, this PR pulls out all the code changes from there in regards to removing the credential reuse functionality. That functionality is no longer needed with the changes being made there to work with global Providers.

Note I'm leaving this PR in draft mode for now as we're paused on #1038 while we work to get a few more things across the finish line and released. Once that's done and we're ready to look at #1038 again, I'll open this PR and it can be reviewed/merged prior to reviewing #1038 again, as it will help reduce the number of files/line changes in that PR.

How to test the Change

Ensure the credential reuse modal no longer appears but that you can still properly set credentials for all existing Feature/Provider combos

Changelog Entry

Removed - Credential reuse functionality

Credits

Props @dkotter

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added Critical Flows, Test Cases, and/or End-to-End Tests to cover my change.
• All new and existing tests pass.

[github-actions]

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