schemaStorage(ticdc): remove schemaVersion in schemaStorage (#11869)

[ti-chi-bot]

This is an automated cherry-pick of #11869

What problem does this PR solve?

Issue Number: close #11868

What is changed and how it works?

This PR removes the SchemaVersion field and its associated logic from the schemaStorage component in TiCDC. The change is part of an effort to remove schema change checking and reduce redundant logic.

Related to #11733.

Check List

Tests

• Unit test
• Integration test

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]

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[ti-chi-bot]

@ti-chi-bot: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
jenkins-ticdc/verify	7796345	link	true	/test verify

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