br: Fix unstable s3 test (again) (#33666)

[ti-srebot]

cherry-pick #33666 to release-5.3
You can switch your code base to this Pull Request by using git-extras:

# In tidb repo:
git pr https://github.com/pingcap/tidb/pull/33682

After apply modifications, you can push your change to this PR via:

git push [email protected]:ti-srebot/tidb.git pr/33682:release-5.3-b857293155f3

---

Signed-off-by: Yu Juncen [email protected]

What problem does this PR solve?

Issue Number: close #33644

Problem Summary:

#33610 ignored a priority of operator. Which doesn't really fixed the problem.

What is changed and how it works?

Added a bracket to the conditions. (Bash is awesome!)

Check List

Tests

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

Release note

None

[ti-chi-bot]

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[ti-srebot]

/run-all-tests

[ti-srebot]

@YuJuncen you're already a collaborator in bot's repo.

[ti-chi-bot]

This pull request is closed because its related version has closed automatic cherry-picking.
If it's still needed, you can reopen it or just regenerate it using bot,
see:

https://prow.tidb.net/command-help#cherrypick
https://book.prow.tidb.net/#/plugins/cherrypicker