sink(ticdc): remove usless ReplicaID field

[Rustin170506]

What problem does this PR solve?

Issue Number: ref #5928
See: #6109 (comment)

What is changed and how it works?

Remove useless ReplicaID field. We can safely remove it because this default branch.

Check List

Tests

No need, just remove code.

Questions

Will it cause performance regression or break compatibility?

No

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

No

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• CharlesCheung96
• overvenus

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[codecov-commenter]

Codecov Report

Merging #6197 (6f53380) into master (ef587e6) will decrease coverage by 0.3868%.
The diff coverage is 62.8132%.

Flag	Coverage Δ
cdc	63.8081% <67.6077%> (-0.8766%)	⬇️
dm	51.9504% <49.6350%> (+0.0613%)	⬆️
engine	62.5492% <59.4847%> (+0.0152%)	⬆️

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

@@               Coverage Diff                @@
##             master      #6197        +/-   ##
================================================
- Coverage   58.4193%   58.0324%   -0.3869%     
================================================
  Files           711        708         -3     
  Lines         84205      83374       -831     
================================================
- Hits          49192      48384       -808     
- Misses        30540      30647       +107     
+ Partials       4473       4343       -130     

[Rustin170506]

/merge

[ti-chi-bot]

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

Commit hash: 6f53380

[Rustin170506]

/run-verify