build(deps): bump com.diffplug.spotless:spotless-maven-plugin

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]

client-java-contrib/admissionreview/pom.xml

@@ -37,7 +37,7 @@
             <plugin>
                 <groupId>com.diffplug.spotless</groupId>
                 <artifactId>spotless-maven-plugin</artifactId>
-                <version>3.3.0</version>
+                <version>3.4.0</version>
                 <configuration>
                     <skip>true</skip>
                 </configuration>

fluent/pom.xml

@@ -39,7 +39,7 @@
             <plugin>
                 <groupId>com.diffplug.spotless</groupId>
                 <artifactId>spotless-maven-plugin</artifactId>
-                <version>3.3.0</version>
+                <version>3.4.0</version>
                 <configuration>
                     <skip>true</skip>
                 </configuration>

pom.xml

@@ -485,7 +485,7 @@
       <plugin>
         <groupId>com.diffplug.spotless</groupId>
         <artifactId>spotless-maven-plugin</artifactId>
-        <version>3.3.0</version>
+        <version>3.4.0</version>
         <configuration>
           <formats>
             <!-- common settings -->