Update dependency checkstyle to v10.21.3

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
checkstyle (source)	10.21.2 -> 10.21.3

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Release Notes

checkstyle/checkstyle (checkstyle)

v10.21.3

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Configuration

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[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

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (311f25b) to head (b2c4463).
Report is 2 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##                main      #280   +/-   ##
===========================================
  Coverage     100.00%   100.00%           
  Complexity       360       360           
===========================================
  Files             65        65           
  Lines           1215      1215           
  Branches         170       170           
===========================================
  Hits            1215      1215           

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