[To dev/1.3] Pipe: Fixed the bug that the parent class loader may wrongly load ext pipe plugins (#17580)

[Caideyipi]

Description

As the title said.

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This PR has:

• been self-reviewed.
  • concurrent read
  • concurrent write
  • concurrent read and write
• added documentation for new or modified features or behaviors.
• added Javadocs for most classes and all non-trivial methods.
• added or updated version, license, or notice information
• added comments explaining the "why" and the intent of the code wherever would not be obvious
  for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold
  for code coverage.
• added integration tests.
• been tested in a test IoTDB cluster.

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Key changed/added classes (or packages if there are too many classes) in this PR

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.2% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

❌ Patch coverage is 94.44444% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 41.61%. Comparing base (04e6684) to head (3ae31fd).

Files with missing lines	Patch %	Lines
...pe/agent/plugin/service/PipePluginClassLoader.java	94.44%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             dev/1.3   #17600      +/-   ##
=============================================
- Coverage      41.62%   41.61%   -0.02%     
  Complexity       234      234              
=============================================
  Files           3610     3610              
  Lines         238026   238043      +17     
  Branches       28892    28896       +4     
=============================================
- Hits           99086    99063      -23     
- Misses        138940   138980      +40     

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