Upgrade maven-pmd-plugin to 3.13.0

Change-Id: I6e20b77db743cd8578aa1f8688f893b746e861d1
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

pom.xml

@@ -298,7 +298,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-pmd-plugin</artifactId>
-          <version>3.12.0</version>
+          <version>3.13.0</version>
           <configuration>
             <sourceEncoding>utf-8</sourceEncoding>
             <minimumTokens>100</minimumTokens>