feat: add log for searcher plugin

[gaius-qi]

Description

This pull request includes several changes to improve error logging, optimize code, and adjust default settings. The most important changes are summarized below:

Enhancements to logging:

• manager/searcher/searcher.go: Updated the logging statement to use logger.Warnf instead of logger.Info when loading the searcher plugin fails, providing more context about the error.

Code optimization:

• manager/searcher/searcher.go: Simplified the calculateMultiElementAffinityScore function by replacing a conditional block with a single min function and modifying the loop to use range.

Adjustments to default settings:

• pkg/rpc/scheduler/server/server.go: Reduced the default QPS and burst values for the gRPC server from 20,000 and 30,000 to 1,000, respectively.

Related Issue

Motivation and Context

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation Update (if none of the other choices apply)

Checklist

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 34.51%. Comparing base (e8166e4) to head (324fe27).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3942      +/-   ##
==========================================
- Coverage   34.53%   34.51%   -0.02%     
==========================================
  Files         339      339              
  Lines       39943    39937       -6     
==========================================
- Hits        13796    13786      -10     
- Misses      25242    25244       +2     
- Partials      905      907       +2     

Flag	Coverage Δ
unittests	34.51% <100.00%> (-0.02%)	⬇️

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

Files with missing lines	Coverage Δ
manager/searcher/searcher.go	73.94% <100.00%> (+2.04%)	⬆️
pkg/rpc/scheduler/server/server.go	100.00% <ø> (ø)

... and 5 files with indirect coverage changes

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