Bump com.diffplug.spotless:spotless-maven-plugin from 3.3.0 to 3.4.0

Bumps [com.diffplug.spotless:spotless-maven-plugin](https://github.com/diffplug/spotless) from 3.3.0 to 3.4.0.
- [Release notes](https://github.com/diffplug/spotless/releases)
- [Changelog](https://github.com/diffplug/spotless/blob/main/CHANGES.md)
- [Commits](diffplug/spotless@lib/3.3.0...maven/3.4.0)

---
updated-dependencies:
- dependency-name: com.diffplug.spotless:spotless-maven-plugin
  dependency-version: 3.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pom.xml

@@ -235,7 +235,7 @@
     <taglist-maven-plugin.version>3.2.2</taglist-maven-plugin.version>
     <versions-maven-plugin.version>2.21.0</versions-maven-plugin.version>
     <sisu-maven-plugin.version>1.0.0</sisu-maven-plugin.version>
-    <spotless-maven-plugin.version>3.3.0</spotless-maven-plugin.version>
+    <spotless-maven-plugin.version>3.4.0</spotless-maven-plugin.version>
     <palantirJavaFormat.version>2.89.0</palantirJavaFormat.version>
     <project.build.outputTimestamp>2026-03-14T13:54:36Z</project.build.outputTimestamp>
     <!-- mono-module doesn't require site:stage for scm-publish -->