Drop unused commons-lang 2.6 from management (#661)

Author: elilja

pom.xml

@@ -202,11 +202,6 @@
           </exclusion>
         </exclusions>
       </dependency>
-      <dependency>
-        <groupId>commons-lang</groupId>
-        <artifactId>commons-lang</artifactId>
-        <version>2.6</version>
-      </dependency>
       <dependency>
         <groupId>org.apache.maven.plugin-testing</groupId>
         <artifactId>maven-plugin-testing-harness</artifactId>