tests: fix more events could be sent after a table is removed

[amyangfei]

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]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• hi-rustin
• overvenus

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[Rustin170506]

Unstable test fixer! 👍

[overvenus]

/merge

[ti-chi-bot]

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

Commit hash: 27fe1e6

[amyangfei]

/run-unit-tests

[amyangfei]

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

[codecov-commenter]

Codecov Report

Merging #2569 (efd3b62) into master (48779ba) will increase coverage by 2.4689%.
The diff coverage is 65.5660%.

@@               Coverage Diff                @@
##             master      #2569        +/-   ##
================================================
+ Coverage   56.0169%   58.4858%   +2.4689%     
================================================
  Files           169        165         -4     
  Lines         20567      18955      -1612     
================================================
- Hits          11521      11086       -435     
+ Misses         7921       6853      -1068     
+ Partials       1125       1016       -109     

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #2577.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #2578.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #2579.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #2580.