`cleanupCode` only removes the first line of a `@DemoSource` annotation https://github.com/FlowingCode/CommonsDemo/blob/daa2cb3fc064953b05fb7bd32e9c90b9286861c0/src/main/resources/META-INF/resources/frontend/code-viewer.ts#L332 https://github.com/FlowingCode/GoogleMapsAddon/blob/4282e8e6d2e0a441e8d3b0e5fc480d03ab9a4410/src/test/java/com/flowingcode/vaadin/addons/googlemaps/GeolocationDemo.java#L34C1-L36C45 
