[DNM] changefeed(ticdc): refactor new changefeed method attach the reactor directly

[3AceShowHand]

What problem does this PR solve?

Issue Number: close #xxx

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]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• asddongmen
• zhaoxinyu

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[3AceShowHand]

/run-all-tests

[3AceShowHand]

/run-all-tests

[codecov-commenter]

Codecov Report

Merging #6740 (2a25636) into master (2ea67ba) will increase coverage by 0.1615%. The diff coverage is 67.7444%.

Flag	Coverage Δ
cdc	66.0350% <62.3390%> (+0.1669%)	:arrow_up:
dm	52.1065% <72.9729%> (+0.0648%)	:arrow_up:
engine	62.8005% <85.4961%> (+0.2644%)	:arrow_up:

Flags with carried forward coverage won't be shown. Click here to find out more.

@@               Coverage Diff                @@
##             master      #6740        +/-   ##
================================================
+ Coverage   59.2138%   59.3754%   +0.1615%     
================================================
  Files           780        783         +3     
  Lines         88405      89116       +711     
================================================
+ Hits          52348      52913       +565     
- Misses        31415      31532       +117     
- Partials       4642       4671        +29     

[3AceShowHand]

/merge

[ti-chi-bot]

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

Commit hash: 2a25636476df0195b3bf9453088b27ab56b60c91

[3AceShowHand]

/run-verify-ci

[3AceShowHand]

/run-leak-test /run-integration-test

[3AceShowHand]

/run-dm-compatibility-test