minor cleanup of jetty-9 pom
minor cleanup of jetty-9 pom

ludoch/appengine-java-vm-runtime,GoogleCloudPlatform/openjdk-runtime,aozarov/appengine-java-vm-runtime,GoogleCloudPlatform/appengine-java-vm-runtime,GoogleCloudPlatform/jetty-runtime,GoogleCloudPlatform/jetty-runtime,GoogleCloudPlatform/openjdk-runtime,GoogleCloudPlatform/jetty-runtime,jetty-project/appengine-java-vm-runtime,ludoch/appengine-java-vm-runtime,jetty-project/appengine-java-vm-runtime,GoogleCloudPlatform/jetty-runtime,GoogleCloudPlatform/appengine-java-vm-runtime,ludoch/appengine-java-vm-runtime,aozarov/appengine-java-vm-runtime,aozarov/appengine-java-vm-runtime,GoogleCloudPlatform/appengine-java-vm-runtime,jetty-project/appengine-java-vm-runtime,GoogleCloudPlatform/openjdk-runtime