Update spotlessPluginGradle to v8.9.0

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
com.diffplug.spotless	8.8.0 → 8.9.0
com.diffplug.spotless:com.diffplug.spotless.gradle.plugin	8.8.0 → 8.9.0

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.89%. Comparing base (f45df77) to head (e737d22).

Additional details and impacted files

@@ Coverage Diff @@## main #751 +/- ##
=======================================
Coverage 80.89% 80.89% =======================================
Files 41 41 Lines 916 916 Branches 174 174 =======================================
Hits 741 741 Misses 107 107 Partials 68 68 

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