public AnnotatedStage a_stage_that_is_a_spring_component() {
        return this;
    }
example that uses {@link JGivenStage} to initialize a class as
a spring bean and a JGiven stage (i.e. with automatically attached
method interceptors)
jgiven-spring-junit4/src/test/java/com/tngtech/jgiven/integration/spring/test/AnnotatedStage.java