Update to Sling Parent 23

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1687500 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index 8107bc0..a3d0d3a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -23,7 +23,7 @@
   <parent>
     <groupId>org.apache.sling</groupId>
     <artifactId>sling</artifactId>
-    <version>22</version>
+    <version>23</version>
     <relativePath/>
   </parent>