Pipe: Fixed the OPC UA bug that drop pipe may not erase the client

[Caideyipi]

Description

As the title said.

---

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
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 39.87%. Comparing base (89c2af8) to head (1b028b8).
⚠️ Report is 7 commits behind head on master.

Files with missing lines	Patch %	Lines
...e/iotdb/db/pipe/sink/protocol/opcua/OpcUaSink.java	50.00%	9 Missing ⚠️

Additional details and impacted files

@@ Coverage Diff @@## master #17510 +/- ##
============================================
- Coverage 39.87% 39.87% -0.01% 
Complexity 312 312 ============================================
Files 5137 5137 Lines 347145 347143 -2 Branches 44246 44246 ============================================
- Hits 138413 138407 -6 - Misses 208732 208736 +4 

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