*: only output log when error is non-nil

[xhebox]

What problem does this PR solve?

Issue Number: close #53349

Problem Summary: As title.

Check List

Tests

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

  • [ ] I checked and no code files have been changed.

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

[tiprow[bot]]

Hi @xhebox. Thanks for your PR.

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[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Defined2014, YangKeao

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Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/pingcap/tidb/blob/master/OWNERS)~~ [Defined2014,YangKeao] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[ti-chi-bot[bot]]

[LGTM Timeline notifier]

Timeline:

• 2024-05-17 05:38:42.658584059 +0000 UTC m=+1804476.415719639: :ballot_box_with_check: agreed by Defined2014.
• 2024-05-17 05:39:59.781866606 +0000 UTC m=+1804553.539002172: :ballot_box_with_check: agreed by YangKeao.

[Defined2014]

/run-check-issue-triage-complete

[xhebox]

/check-issue-triage-complete

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 5 lines in your changes are missing coverage. Please review.

Project coverage is 73.8438%. Comparing base (1c4a9c6) to head (ef489c6). Report is 1 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #53350 +/- ## ================================================ + Coverage 72.4996% 73.8438% +1.3442% ================================================ Files 1505 1523 +18 Lines 429646 435317 +5671 ================================================ + Hits 311492 321455 +9963 + Misses 98849 93956 -4893 - Partials 19305 19906 +601 ``` | [Flag](https://app.codecov.io/gh/pingcap/tidb/pull/53350/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | Coverage Δ | | |---|---|---| | [integration](https://app.codecov.io/gh/pingcap/tidb/pull/53350/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `49.1264% <0.0000%> (?)` | | | [unit](https://app.codecov.io/gh/pingcap/tidb/pull/53350/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `71.4382% <0.0000%> (+0.0392%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap#carryforward-flags-in-the-pull-request-comment) to find out more. | [Components](https://app.codecov.io/gh/pingcap/tidb/pull/53350/components?src=pr&el=components&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | Coverage Δ | | |---|---|---| | [dumpling](https://app.codecov.io/gh/pingcap/tidb/pull/53350/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `53.9957% <ø> (ø)` | | | [parser](https://app.codecov.io/gh/pingcap/tidb/pull/53350/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `∅ <ø> (∅)` | | | [br](https://app.codecov.io/gh/pingcap/tidb/pull/53350/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `43.3054% <ø> (+1.8809%)` | :arrow_up: |

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #53354.