Find @Async methods declared in a @Configuration class

Marks an @Async annotation on a method declared directly in a class that is itself annotated @Configuration. SonarQube reports these because @Async is not supported on methods of a @Configuration class. Whether to move the method to another bean or to drop the annotation is left to the author. Classes that are configuration classes only through a meta-annotation such as @SpringBootApplication, an @Async written after the type parameters, interfaces, enums, records, and methods of anonymous classes or of nested classes not themselves annotated @Configuration are not marked. Test sources are not searched.