*: enable errcheck

[okJiang]

What problem does this PR solve?

Issue Number: Ref https://github.com/tikv/pd/issues/1919

What is changed and how does it work?

Check List

Tests

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

Code changes

• Has the configuration change
• Has HTTP API interfaces changed (Don't forget to add the declarative for the new API)
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• PR to update pingcap/docs/pingcap/docs-cn:
• PR to update pingcap/tiup:
• Need to cherry-pick to the release branch

Release note

None.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 47.22222% with 19 lines in your changes missing coverage. Please review.

Project coverage is 77.28%. Comparing base (9dff6e6) to head (b2b5ab6). Report is 1 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #8277 +/- ## ========================================== - Coverage 77.35% 77.28% -0.08% ========================================== Files 470 470 Lines 61376 61385 +9 ========================================== - Hits 47478 47439 -39 - Misses 10336 10388 +52 + Partials 3562 3558 -4 ``` | [Flag](https://app.codecov.io/gh/tikv/pd/pull/8277/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=tikv) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/tikv/pd/pull/8277/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=tikv) | `77.28% <47.22%> (-0.08%)` | :arrow_down: | 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=tikv#carryforward-flags-in-the-pull-request-comment) to find out more.

[okJiang]

/retest

[JmPotato]

/merge

[ti-chi-bot[bot]]

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[JmPotato]

/approve

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: JmPotato, rleungx

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[ti-chi-bot[bot]]

[LGTM Timeline notifier]

Timeline:

• 2024-06-13 08:11:51.827623148 +0000 UTC m=+625065.880935095: :ballot_box_with_check: agreed by rleungx.
• 2024-06-14 06:33:08.722633628 +0000 UTC m=+705542.775945553: :ballot_box_with_check: agreed by JmPotato.

[rleungx]

/merge

[ti-chi-bot[bot]]

@rleungx: We have migrated to builtin LGTM and approve plugins for reviewing.

👉 Please use /approve when you want approve this pull request.

The changes announcement: Proposal: Strengthen configuration change approval.

Instructions for interacting with me using PR comments are available [here](https://prow.tidb.net/command-help). If you have questions or suggestions related to my behavior, please file an issue against the [ti-community-infra/tichi](https://github.com/ti-community-infra/tichi/issues/new?title=Prow%20issue:) repository.