launchpad/testing-war: really fix the rat configuration

The changes in r1762835 were not sufficient.

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1762911 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index b9f046a..c77cf73 100644
--- a/pom.xml
+++ b/pom.xml
@@ -182,7 +182,7 @@
                 <artifactId>apache-rat-plugin</artifactId>
                 <configuration>
                     <excludes combine.children="append">
-                        <exclude>sling</exclude>
+                        <exclude>sling/*</exclude>
                     </excludes>
                 </configuration>
             </plugin>