Bump maven-pmd-plugin from 3.19.0 to 3.20.0

Bumps [maven-pmd-plugin](https://github.com/apache/maven-pmd-plugin) from 3.19.0 to 3.20.0.
- [Release notes](https://github.com/apache/maven-pmd-plugin/releases)
- [Commits](https://github.com/apache/maven-pmd-plugin/compare/maven-pmd-plugin-3.19.0...maven-pmd-plugin-3.20.0)

---
updated-dependencies:
- dependency-name: org.apache.maven.plugins:maven-pmd-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/pom.xml b/pom.xml
index 6950b62..643cbaf 100644
--- a/pom.xml
+++ b/pom.xml
@@ -287,7 +287,7 @@
       <plugin>
         <artifactId>maven-pmd-plugin</artifactId>
         <!-- Later versions require Java 1.6+ -->
-        <version>3.19.0</version>
+        <version>3.20.0</version>
         <configuration>
           <linkXRef>true</linkXRef>
           <sourceEncoding>utf-8</sourceEncoding>