infoschema: try on each PD member until one succeeds or all fail (#35285)

[ti-srebot]

cherry-pick #35285 to release-4.0
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/35501

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

git push git@github.com:ti-srebot/tidb.git pr/35501:release-4.0-7bd892340dd1

---

Signed-off-by: JmPotato ghzpotato@gmail.com

What problem does this PR solve?

Issue Number: close #35268.

What is changed and how it works?

GetPDServerInfo will try on each PD member until one succeeds or all fail.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

Before:

After:

Release note

None

[ti-chi-bot]

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[ti-chi-bot]

@ti-srebot: This cherry pick PR is for a release branch and has not yet been approved by release team.
Adding the do-not-merge/cherry-pick-not-approved label.

To merge this cherry pick, it must first be approved by the collaborators.

AFTER it has been approved by collaborators, please ping the release team in a comment to request a cherry pick review.

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[ti-srebot]

/run-all-tests

[ti-srebot]

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

[JmPotato]

/close

[ti-chi-bot]

@JmPotato: Closed this PR.

In response to this:

/close

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.