util/traceevent: make flaky test TestFlightRecorder stable (#65317)

[ti-chi-bot]

This is an automated cherry-pick of #65317

What problem does this PR solve?

Issue Number: close #65230

Problem Summary:

What changed and how does it work?

The test use global variable IsEnabled(category) and other tests also update that variable, so the test is unstable.
I just moving category to GetFlightRecorder().enabledCategories to avoid conflict, no other tests in this package are updating the same FlightRecorder structure at the same time.

This PR just fix the flaky test, later I should do some refactor.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

This cherry pick PR is for a release branch and has not yet been approved by triage owners.
Adding the do-not-merge/cherry-pick-not-approved label.

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