Merge pull request #89 from apache/dependabot/maven/org.apache.maven.plugins-maven-pmd-plugin-3.21.2

Bump org.apache.maven.plugins:maven-pmd-plugin from 3.20.0 to 3.21.2
diff --git a/pom.xml b/pom.xml
index 29682ac..bbb1065 100644
--- a/pom.xml
+++ b/pom.xml
@@ -287,7 +287,7 @@
       <plugin>
         <artifactId>maven-pmd-plugin</artifactId>
         <!-- Later versions require Java 1.6+ -->
-        <version>3.20.0</version>
+        <version>3.21.2</version>
         <configuration>
           <linkXRef>true</linkXRef>
           <sourceEncoding>utf-8</sourceEncoding>