PROTON-2944: update to apache parent pom 39

Author: gemmellr

pom.xml

@@ -20,7 +20,7 @@
   <parent>
     <groupId>org.apache</groupId>
     <artifactId>apache</artifactId>
-    <version>27</version>
+    <version>39</version>
   </parent>
   <modelVersion>4.0.0</modelVersion>