log-backup: do not rewrite shortvalue iif the value is rollback record.

[joccau]

What problem does this PR solve?

Issue Number: close #39575

Problem Summary:

• Failed to unmarsher short-value into DbInfo because the meta-kv is rollback record.

What is changed and how it works?

• Skip rewrite value if the meta-kv is rollback record.

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.

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• 3pointer
• YuJuncen

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[joccau]

/merge

[ti-chi-bot]

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

Commit hash: 8f61a6f

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #39599.

[sre-bot]

TiDB MergeCI notify

✅ Well Done! New fixed [1] after this pr merged.

CI Name	Result	Duration	Compare with Parent commit
idc-jenkins-ci/integration-cdc-test	🔴 failed 1, success 39, total 40	25 min	Existing failure
idc-jenkins-ci-tidb/integration-common-test	🔴 failed 1, success 16, total 17	15 min	Existing failure
idc-jenkins-ci-tidb/common-test	🔴 failed 1, success 10, total 11	11 min	Existing failure
idc-jenkins-ci-tidb/integration-ddl-test	✅ all 6 tests passed	4 min 42 sec	Fixed
idc-jenkins-ci-tidb/sqllogic-test-1	🟢 all 26 tests passed	6 min 3 sec	Existing passed
idc-jenkins-ci-tidb/tics-test	🟢 all 1 tests passed	5 min 51 sec	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-2	🟢 all 28 tests passed	5 min 42 sec	Existing passed
idc-jenkins-ci-tidb/mybatis-test	🟢 all 1 tests passed	3 min 54 sec	Existing passed
idc-jenkins-ci-tidb/integration-compatibility-test	🟢 all 1 tests passed	2 min 34 sec	Existing passed
idc-jenkins-ci-tidb/plugin-test	🟢 build success, plugin test success	4min	Existing passed

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #39613.