PDFBOX-5660: update commons-net

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1932447 13f79535-47bb-0310-9956-ffa450edef68

Author: THausherr

examples/pom.xml

@@ -105,7 +105,7 @@
     <dependency>
       <groupId>commons-net</groupId>
       <artifactId>commons-net</artifactId>
-      <version>3.12.0</version>
+      <version>3.13.0</version>
       <scope>test</scope>
     </dependency>
     <dependency>