Examples: Upgrade Jetty version. (#1859)

Author: songy23

examples/build.gradle

@@ -36,7 +36,7 @@ version = "0.21.0-SNAPSHOT" // CURRENT_OPENCENSUS_VERSION
 def opencensusVersion = "0.20.0" // LATEST_OPENCENSUS_RELEASE_VERSION
 def grpcVersion = "1.19.0" // CURRENT_GRPC_VERSION
 def prometheusVersion = "0.6.0"
-def jettyVersion = "9.4.12.v20180830"
+def jettyVersion = "9.4.17.v20190418"
 
 tasks.withType(JavaCompile) {
     sourceCompatibility = '1.8'

examples/pom.xml

@@ -11,7 +11,7 @@
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <!-- change to the version you want to use. -->
-    <jetty.version>9.4.12.v20180830</jetty.version>
+    <jetty.version>9.4.17.v20190418</jetty.version>
     <opencensus.version>0.20.0</opencensus.version><!-- LATEST_OPENCENSUS_RELEASE_VERSION -->
     <grpc.version>1.19.0</grpc.version><!-- CURRENT_GRPC_VERSION -->
   </properties>