With this runtime annotation, a developer is able to mark a controller's
method in order to not render a page after its execution.
It's only valid to methods that return void, because methods that return an
object, will always serialize that object in the response.
Methods that don't return anything have to be annotated so the framework is
able to know what to do after the execution. If it's annotated with
DoNotRenderPage, the framework will return a HTTP status code 204 (No content),
if it isn't annotated, the framework will search for a page to render.