Refactor admin action test suite

[Joerger]

Refactor admin action tctl tests to use testify/suite for shared setup/teardown.

This should unblock my open PRs (ex: #35464) where the flaky test detector is timing out trying to diff all test cases.

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[zmb3]

Why exactly do we need this? It looks like we now have 3 or 4 levels of nested subtests which seems a bit much.

[Joerger]

@zmb3 Without this refactor, the flaky test detector is timing out on my PRs trying to run all test subcases of TestAdminActionMFA. The flaky test detector has a condition for testify/suites where it only runs the changed subcases instead of all of them.

As for the deeper sub cases, I could remove a couple layers if we think it's too confusing and not worth the shared code.

[zmb3]

The flaky test detector has a condition for testify/suites where it only runs the changed subcases instead of all of them.

Got it - that's the piece I was missing. Thanks for clarifying.

[Joerger]

@r0mant @zmb3 Can I get a flaky test skip?

[r0mant]

/excludeflake *