fix: [24]Replace outer lock with concurrent map (#37817)

[XuanYang-cn]

See also: #37493
pr: #37817

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: XuanYang-cn
To complete the pull request process, please assign czs007 after the PR has been reviewed.
You can assign the PR to them by writing /assign @czs007 in a comment when ready.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• internal/datanode/OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[mergify]

@XuanYang-cn E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

[codecov]

Codecov Report

Attention: Patch coverage is 93.54839% with 2 lines in your changes missing coverage. Please review.

Project coverage is 80.57%. Comparing base (4aca68a) to head (53f2d80).
Report is 1 commits behind head on 2.4.

Files with missing lines	Patch %	Lines
internal/datanode/writebuffer/manager.go	91.66%	0 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              2.4   #37897      +/-   ##
==========================================
+ Coverage   72.24%   80.57%   +8.33%     
==========================================
  Files        1069     1069              
  Lines      166979   166946      -33     
==========================================
+ Hits       120641   134525   +13884     
+ Misses      41919    27995   -13924     
- Partials     4419     4426       +7     

Files with missing lines	Coverage Δ
internal/datanode/writebuffer/write_buffer.go	75.96% <100.00%> (-0.90%)	⬇️
internal/datanode/writebuffer/manager.go	93.15% <91.66%> (+0.57%)	⬆️

... and 231 files with indirect coverage changes

---- 🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests