upgraded changes plugin as the old version threw errors

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/ognl/trunk@1519856 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index 59657f7..00d73c2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -329,7 +329,7 @@
           <plugin>
             <groupId>org.apache.maven.plugins</groupId>
             <artifactId>maven-changes-plugin</artifactId>
-            <version>2.3</version>
+            <version>2.8</version>
             <configuration>
               <xmlPath>${basedir}/src/changes/changes.xml</xmlPath>
               <issueLinkTemplate>%URL%/%ISSUE%</issueLinkTemplate>