CI: update config for sync diff (#3435)

[ti-chi-bot]

This is an automated cherry-pick of #3435

What problem does this PR solve?

After pingcap/tidb-tools#546 merged. sync-diff has breaking config change. so the dm tests need to update.

What is changed and how it works?

change dm test sync-diff config to adapt new config.

Check List

Tests

• Integration test

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation
• Need to update key monitor metrics in both TiCDC document and official document

Release note

None

[ti-chi-bot]

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[ti-chi-bot]

@ti-chi-bot: 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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[glorv]

closed in favor of #3491