Update dependency com.diffplug.spotless:spotless-plugin-gradle to v8.6.0

[mend-for-github-com]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
com.diffplug.spotless:spotless-plugin-gradle	8.4.0 → 8.6.0

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Configuration

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.57%. Comparing base (0b5b7ad) to head (9214111).

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #1402   +/-   ##
=========================================
  Coverage     78.57%   78.57%           
  Complexity     1315     1315           
=========================================
  Files           106      106           
  Lines          6045     6045           
  Branches        647      647           
=========================================
  Hits           4750     4750           
  Misses         1004     1004           
  Partials        291      291           

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