kv(ticdc): Remove store connect backoff (#9740)

[sdojjy]

close #9741

What problem does this PR solve?

Issue Number: close #xxx

What is changed and how it works?

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Tests

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• Integration test
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[sdojjy]

/retest-required

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: 3AceShowHand, asddongmen

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-12-29 06:12:19.842300431 +0000 UTC m=+1805430.879527355: ☑️ agreed by asddongmen.
• 2023-12-29 08:44:28.880856585 +0000 UTC m=+1814559.918083511: ☑️ agreed by 3AceShowHand.