fix: Limit the concurrency of channel tasks

[bigsheeper]

Limit the maximum concurrency of channel tasks for each DataNode to prevent excessive subscriptions from causing DataNode OOM.

issue: #37665

[mergify]

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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.51%. Comparing base (3cdb485) to head (cd2cc06).
Report is 26 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #37740       +/-   ##
===========================================
+ Coverage   68.91%   82.51%   +13.59%     
===========================================
  Files         290     1067      +777     
  Lines       25471   165287   +139816     
===========================================
+ Hits        17553   136380   +118827     
- Misses       7918    23478    +15560     
- Partials        0     5429     +5429     

Components	Coverage Δ
Client	61.25% <ø> (∅)
Core	∅ <ø> (∅)
Go	83.21% <100.00%> (∅)

Files with missing lines	Coverage Δ
internal/datacoord/channel_manager.go	87.66% <100.00%> (ø)
pkg/util/paramtable/component_param.go	98.35% <100.00%> (ø)

... and 1355 files with indirect coverage changes

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[czs007]

/run-cpu-e2e

[mergify]

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

[bigsheeper]

/run-cpu-e2e

[czs007]

/approve
/lgtm

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: bigsheeper, czs007

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• configs/OWNERS [czs007]
• internal/datacoord/OWNERS [czs007]
• pkg/util/OWNERS [czs007]

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