Bump com.diffplug.spotless from 8.3.0 to 8.4.0 (#147)

Bumps com.diffplug.spotless from 8.3.0 to 8.4.0.

---
updated-dependencies:
- dependency-name: com.diffplug.spotless
  dependency-version: 8.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

build.gradle.kts

@@ -12,7 +12,7 @@ val ktfmtVersion = "0.44"
 plugins {
     kotlin("jvm") version "2.3.20"
     id("com.github.ben-manes.versions") version "0.53.0"
-    id("com.diffplug.spotless") version "8.3.0"
+    id("com.diffplug.spotless") version "8.4.0"
     id("com.vanniktech.maven.publish") version "0.36.0"
 }