Adds XML syntax highlighting to Extended Usage example in README.
@@ -128,7 +128,7 @@ In this configuration, the image is:
* Pushed to `localhost:5000/my-image:built-with-jib`
* Runs by calling `java -Xms512m -Xdebug -Xmy:flag=jib-rules -cp app/libs/*:app/resources:app/classes mypackage.MyApp`
-```
+```xml
<configuration>
<from>openjdk:alpine</from>
<registry>localhost:5000</registry>
