Update dependency com.diffplug.spotless:spotless-plugin-gradle to v8.4.0

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
com.diffplug.spotless:spotless-plugin-gradle	8.2.1 → 8.4.0

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.76%. Comparing base (aa0fbd7) to head (ca39dda).
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Additional details and impacted files

@@            Coverage Diff            @@
##             master     #131   +/-   ##
=========================================
  Coverage     90.76%   90.76%           
  Complexity      265      265           
=========================================
  Files           118      118           
  Lines           671      671           
  Branches         60       60           
=========================================
  Hits            609      609           
  Misses           47       47           
  Partials         15       15           

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