Update to latest parent pom
diff --git a/pom.xml b/pom.xml
index bec5922..c1ad9f2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -13,7 +13,7 @@
     <parent>
         <groupId>org.apache.sling</groupId>
         <artifactId>sling</artifactId>
-        <version>35</version>
+        <version>39</version>
         <relativePath />
     </parent>