Remove unreferenced dependency on Apache Commons Collection 4

Change-Id: Icb7ac4b2d98bb7e3d8c8792ed26902685debf5c1
diff --git a/pom.xml b/pom.xml
index 829e9f4..0808e42 100644
--- a/pom.xml
+++ b/pom.xml
@@ -177,12 +177,6 @@
             </dependency>
 
             <dependency>
-                <groupId>org.apache.commons</groupId>
-                <artifactId>commons-collections4</artifactId>
-                <version>4.0</version>
-            </dependency>
-
-            <dependency>
                 <groupId>org.codehaus.jackson</groupId>
                 <artifactId>jackson-core-asl</artifactId>
                 <version>1.9.13</version>