sourcemanager(ticdc): close all pullers asyncrhonsly to prevent block too long

[3AceShowHand]

What problem does this PR solve?

Issue Number: ref #11638

What is changed and how it works?

Check List

Tests

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

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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[ti-chi-bot]

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[ti-chi-bot]

@3AceShowHand: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-cdc-integration-mysql-test	f1b9c34	link	true	/test cdc-integration-mysql-test

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