ddl: prevent returning zero schema version for alter sequence (#36277)

[ti-srebot]

cherry-pick #36277 to release-6.1
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# In tidb repo:
git pr https://github.com/pingcap/tidb/pull/36418

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git push git@github.com:ti-srebot/tidb.git pr/36418:release-6.1-1bc13cd18f85

---

Signed-off-by: AilinKid 314806019@qq.com

What problem does this PR solve?

Issue Number: close #36276

Problem Summary:

What is changed and how it works?

Check List

Tests

• [] Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

ddl: fix alter sequence will generate schemaVer=0 when alter options are the same as the old

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• Defined2014
• xhebox

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[ti-srebot]

/run-all-tests

[ti-srebot]

@AilinKid you're already a collaborator in bot's repo.

[sre-bot]

Code Coverage Details: https://codecov.io/github/pingcap/tidb/commit/630d233fb4f2b2cf8063887d10473ec8d0b3a2ae

[xhebox]

/merge

[ti-chi-bot]

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

Commit hash: 15ce166