Revert "bump to 2.6.4 for maven"

This reverts commit 5d236e31b175790204856afffb7b23ad1a19a078.

pom.xml

@@ -49,7 +49,7 @@
         <dependency>
             <groupId>org.apache.jackrabbit</groupId>
             <artifactId>jackrabbit-webdav</artifactId>
-            <version>2.6.4</version>
+            <version>2.6.3</version>
         </dependency>
 
     </dependencies>