I2D: test-status checks

[rileyajones]

Summary

After tests run in CI they report a status to our custom test-status bot which then shows a message on the PR.

This information is redundant with the information displayed by the CircleCI checks while requiring the maintenance of both the bot and integration with it.

Motivation

CircleCI provides a lot more information about tests and their statuses in a cleaner way without requiring as much of a maintenance burden.

Impact on Existing Users

Realistically none. Some developers may need to discover failed tests differently.

Alternative Implementation

Do not remove the bot and work to reduce the tech debt it contains.

Additional Context

No response

Notifications

/cc @ampproject/wg-approvers

[kristoferbaxter]

Approved!

[rsimha]

+1, approved 👍