cdc: remove unused code and add some logs

[hongyunyan]

What problem does this PR solve?

Issue Number: ref #10457

What is changed and how it works?

1. remove some no longer used code.
2. adjust some logs

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

None

[codecov]

Codecov Report

Merging #10458 (b3fec82) into master (3e9c9de) will decrease coverage by 5.8585%.
Report is 288 commits behind head on master.
The diff coverage is 53.8533%.

Additional details and impacted files

Components	Coverage Δ
cdc	61.8511% <53.8533%> (-1.5558%)	⬇️
dm	51.3045% <ø> (∅)
engine	63.4635% <ø> (∅)

Flag	Coverage Δ
unit	57.5484% <53.8533%> (-5.8585%)	⬇️

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

@@               Coverage Diff                @@
##             master     #10458        +/-   ##
================================================
- Coverage   63.4069%   57.5484%   -5.8585%     
================================================
  Files           392        849       +457     
  Lines         51067     125953     +74886     
================================================
+ Hits          32380      72484     +40104     
- Misses        16385      48084     +31699     
- Partials       2302       5385      +3083     

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-01-12 02:33:35.279416894 +0000 UTC m=+583404.863670567: ☑️ agreed by hicqu.
• 2024-01-12 03:23:39.054856283 +0000 UTC m=+586408.639109955: ☑️ agreed by 3AceShowHand.

[hongyunyan]

/check-issue-triage-complete

[hongyunyan]

/test cdc-integration-mysql-test

[ti-chi-bot]

@hongyunyan: The specified target(s) for /test were not found.
The following commands are available to trigger required jobs:

• /test cdc-integration-kafka-test
• /test cdc-integration-mysql-test
• /test cdc-integration-pulsar-test
• /test cdc-integration-storage-test
• /test dm-compatibility-test
• /test dm-integration-test
• /test engine-integration-test
• /test verify
• /test wip-pull-build
• /test wip-pull-check
• /test wip-pull-unit-test-cdc
• /test wip-pull-unit-test-dm
• /test wip-pull-unit-test-engine

Use /test all to run the following jobs that were automatically triggered:

• pingcap/tiflow/ghpr_verify
• pingcap/tiflow/pull_cdc_integration_kafka_test
• pingcap/tiflow/pull_cdc_integration_storage_test
• pingcap/tiflow/pull_cdc_integration_test
• pingcap/tiflow/pull_dm_compatibility_test
• pingcap/tiflow/pull_dm_integration_test
• pingcap/tiflow/pull_engine_integration_test

In response to this:

/test cdc-integration-mysql-test

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[hongyunyan]

/test cdc-integration-mysql-test