Fix calculation problem in first_by aggregation of table model

[Beyyes]

Description

As the title.

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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

[sonarcloud]

Quality Gate failed

Failed conditions
13.6% Duplication on New Code (required ≤ 3%)

See analysis details on SonarCloud

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 25 lines in your changes missing coverage. Please review.

Project coverage is 39.97%. Comparing base (a6cd2b0) to head (1540f53).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
...rce/relational/aggregation/FirstByAccumulator.java	0.00%	23 Missing ⚠️
...urce/relational/aggregation/LastByAccumulator.java	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##             master   #13834   +/-   ##
=========================================
  Coverage     39.96%   39.97%           
  Complexity       71       71           
=========================================
  Files          4144     4144           
  Lines        261744   261744           
  Branches      31902    31902           
=========================================
+ Hits         104607   104624   +17     
+ Misses       157137   157120   -17     

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