tests: fix more events could be sent after a table is removed (#2569)

[ti-chi-bot]

This is an automated cherry-pick of #2569

What problem does this PR solve?

Close #2500

The test failure is caused by sending more row changed events to backend sink when a table sink is removed, the close channel way can't terminate table sink at once.

What is changed and how it works?

Use the context to control table sink lifecycle.

Check List

Tests

• Unit test

Release note

None

[ti-chi-bot]

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[amyangfei]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: b1579a2

[ti-chi-bot]

@ti-chi-bot: Your PR was out of date, I have automatically updated it for you.

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/run-all-tests

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[amyangfei]

/run-integration-tests
/run-unit-tests

[amyangfei]

/run-integration-tests
/run-unit-tests

[amyangfei]

/run-unit-tests