test: Add Flaky Test Plan

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Note

The pull request "test: Add Flaky Test Plan" was created by @philipphofmann but did not reference an issue. Therefore this issue was created for better visibility in external tools like Linear.

Add an extra test plan, Sentry_Flaky, that reruns failing tests 3 times before the test officially fails.

This has the advantage of still running flaky tests in CI over completely disabling them. It's also more efficient than rerunning the entire test suite when a test fails and helps surface new flaky tests.

#skip-changelog

[linear]

COCOA-848