[To dev/1.3] Pipe: Fixed the event clear logic of drop pipe (#17560)

[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
2 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 65.83851% with 55 lines in your changes missing coverage. Please review.
✅ Project coverage is 41.98%. Comparing base (77e9403) to head (de61ca8).
⚠️ Report is 2 commits behind head on dev/1.3.

Files with missing lines	Patch %	Lines
...k/protocol/websocket/WebSocketConnectorServer.java	65.67%	23 Missing ⚠️
...pe/agent/task/connection/BlockingPendingQueue.java	69.56%	7 Missing ⚠️
...rotocol/thrift/async/IoTDBDataRegionAsyncSink.java	70.00%	6 Missing ⚠️
...db/pipe/sink/protocol/websocket/WebSocketSink.java	0.00%	4 Missing ⚠️
...pache/iotdb/commons/pipe/datastructure/Triple.java	73.33%	4 Missing ⚠️
.../payload/evolvable/batch/PipeTabletEventBatch.java	0.00%	3 Missing ⚠️
...ubtask/sink/PipeRealtimePriorityBlockingQueue.java	50.00%	2 Missing ⚠️
.../pipe/agent/task/subtask/sink/PipeSinkSubtask.java	66.66%	2 Missing ⚠️
...nt/task/subtask/sink/PipeSinkSubtaskLifeCycle.java	0.00%	1 Missing ⚠️
...gent/task/subtask/sink/PipeSinkSubtaskManager.java	0.00%	1 Missing ⚠️
... and 2 more

Additional details and impacted files

@@              Coverage Diff              @@
##             dev/1.3   #17619      +/-   ##
=============================================
+ Coverage      41.76%   41.98%   +0.21%     
  Complexity       241      241              
=============================================
  Files           3611     3612       +1     
  Lines         238173   238282     +109     
  Branches       28928    28953      +25     
=============================================
+ Hits           99465   100034     +569     
+ Misses        138708   138248     -460     

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