Bump com.diffplug.spotless:spotless-maven-plugin from 3.0.0 to 3.1.0

Bumps [com.diffplug.spotless:spotless-maven-plugin](https://github.com/diffplug/spotless) from 3.0.0 to 3.1.0.
- [Release notes](https://github.com/diffplug/spotless/releases)
- [Changelog](https://github.com/diffplug/spotless/blob/main/CHANGES.md)
- [Commits](diffplug/spotless@lib/3.0.0...lib/3.1.0)

---
updated-dependencies:
- dependency-name: com.diffplug.spotless:spotless-maven-plugin
  dependency-version: 3.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

pom.xml

@@ -72,7 +72,7 @@
         <spotbugs.version>4.9.8</spotbugs.version>
         <spotbugs-maven-plugin.version>4.9.8.1</spotbugs-maven-plugin.version>
         <findsecbugs.version>1.14.0</findsecbugs.version> <!-- spotbugs plugin for security audits of web apps -->
-        <spotless.version>3.0.0</spotless.version>
+        <spotless.version>3.1.0</spotless.version>
         <therapi.version>0.15.0</therapi.version>
         <!-- Test-related settings -->
         <skipTests>false</skipTests>    <!-- To skip all tests with `-DskipTests` on CLI. -->