fix(deps): update spotless to v8.1.0 (#551)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| com.diffplug.spotless | `8.0.0` -> `8.1.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/com.diffplug.spotless:com.diffplug.spotless.gradle.plugin/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.diffplug.spotless:com.diffplug.spotless.gradle.plugin/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.diffplug.spotless:com.diffplug.spotless.gradle.plugin/8.0.0/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.diffplug.spotless:com.diffplug.spotless.gradle.plugin/8.0.0/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
|
[com.diffplug.spotless:spotless-plugin-gradle](https://redirect.github.com/diffplug/spotless)
| `8.0.0` -> `8.1.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/com.diffplug.spotless:spotless-plugin-gradle/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.diffplug.spotless:spotless-plugin-gradle/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.diffplug.spotless:spotless-plugin-gradle/8.0.0/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.diffplug.spotless:spotless-plugin-gradle/8.0.0/8.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

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gradle/libs.versions.toml

@@ -2,7 +2,7 @@
 springdoc = "2.8.14"
 springBoot = "3.5.7"
 kotest = "6.0.5"
-spotless = "8.0.0"
+spotless = "8.1.0"
 detekt = "1.23.8"
 
 [plugins]