RAT-215: Fix mvn warnings on CI.


git-svn-id: https://svn.apache.org/repos/asf/creadur/rat/trunk@1735922 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index 8477157..2aa0fae 100644
--- a/pom.xml
+++ b/pom.xml
@@ -240,6 +240,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-pmd-plugin</artifactId>
+        <version>3.1</version>
       </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
@@ -304,6 +305,11 @@
         </plugin>
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
+          <artifactId>maven-javadoc-plugin</artifactId>
+          <version>2.10.3</version>
+        </plugin>
+        <plugin>
+          <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-dependency-plugin</artifactId>
           <version>2.8</version>
         </plugin>