upgrade plexus-utils version

git-svn-id: https://svn.apache.org/repos/asf/archiva/redback/redback-components/trunk@1544408 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index 3f7886f..12986f8 100644
--- a/pom.xml
+++ b/pom.xml
@@ -52,7 +52,6 @@
     <dependency>
       <groupId>org.codehaus.plexus</groupId>
       <artifactId>plexus-utils</artifactId>
-      <version>3.0.7</version>
     </dependency>
   </dependencies>