tests/realcluster: using real pd with race (#8270)

[ti-chi-bot]

This is an automated cherry-pick of #8270

What problem does this PR solve?

Issue Number: Ref #7298

What is changed and how does it work?

running with data race

Check List

Tests

• Unit test
• Integration test

Release note

None.

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: Once this PR has been reviewed and has the lgtm label, please assign jmpotato for approval. For more information see the Kubernetes Code Review Process.

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[ti-chi-bot[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.

To merge this cherry pick:

1. It must be approved by the approvers firstly.
2. AFTER it has been approved by approvers, please wait for the cherry-pick merging approval from triage owners.

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