Update maven-pmd-plugin 3.5 -> 3.6.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/csv/trunk@1721768 13f79535-47bb-0310-9956-ffa450edef68

Author: garydgregory

pom.xml

@@ -240,7 +240,7 @@ CSV files of various types.
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-pmd-plugin</artifactId>
-        <version>3.5</version>
+        <version>3.6</version>
         <configuration>
           <targetJdk>${maven.compiler.target}</targetJdk>
         </configuration>