statistics: right deal with error for reading stats from storage

[hawkingrei]

What problem does this PR solve?

Issue Number: ref #57901

Problem Summary:

What changed and how does it work?

if query meets the problem, it will return null error, then it lead to delete stats. it is a bug. so we can first fix this problem first.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• 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.

right deal with error for reading stats from storage to avoid deleting stats

正确处理取统计信息的异常，来防止 stats 被误删除

[codecov]

Codecov Report

Attention: Patch coverage is 25.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 73.3700%. Comparing base (c5d9908) to head (7379502).
Report is 141 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #57914        +/-   ##
================================================
+ Coverage   73.1920%   73.3700%   +0.1780%     
================================================
  Files          1673       1703        +30     
  Lines        461057     469216      +8159     
================================================
+ Hits         337457     344264      +6807     
- Misses       102849     103487       +638     
- Partials      20751      21465       +714     

Flag	Coverage Δ
integration	52.9763% <ø> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.6910% <ø> (ø)
parser	∅ <ø> (∅)
br	45.9562% <ø> (-0.0452%)	⬇️

[hawkingrei]

/retest

[ti-chi-bot]

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[ti-chi-bot]

@hawkingrei: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
idc-jenkins-ci-tidb/mysql-test	7379502	link	true	/test mysql-test
idc-jenkins-ci-tidb/check_dev	7379502	link	true	/test check-dev
idc-jenkins-ci-tidb/check_dev_2	7379502	link	true	/test check-dev2
idc-jenkins-ci-tidb/unit-test	7379502	link	true	/test unit-test

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[tiprow]

@hawkingrei: 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
fast_test_tiprow	7379502	link	true	/test fast_test_tiprow

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