variable: set default tidb_auto_analyze_concurrency as 1

[hawkingrei]

What problem does this PR solve?

Issue Number: close #53460

Problem Summary:

What changed and how does it work?

Reset the default value of auto analyze to 1, thereby maintaining consistency with previous behavior.

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.

None

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.3847%. Comparing base (d55808c) to head (172add9).
Report is 11 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #56226        +/-   ##
================================================
+ Coverage   73.4698%   75.3847%   +1.9148%     
================================================
  Files          1600       1600                
  Lines        443771     443810        +39     
================================================
+ Hits         326038     334565      +8527     
+ Misses        97754      88859      -8895     
- Partials      19979      20386       +407     

Flag	Coverage Δ
integration	49.4807% <ø> (?)
unit	72.4684% <ø> (-0.0667%)	⬇️

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

Components	Coverage Δ
dumpling	52.9567% <ø> (ø)
parser	∅ <ø> (∅)
br	52.9215% <ø> (+7.0589%)	⬆️

[hawkingrei]

/retest

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-23 10:08:08.994349539 +0000 UTC m=+1474158.734773473: ☑️ agreed by winoros.
• 2024-09-24 02:58:19.52788334 +0000 UTC m=+1534769.268307279: ☑️ agreed by qw4990.

[yudongusa]

LGTM and please make sure the document and release note are also revised accordingly.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: qw4990, winoros, yudongusa

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