Fix `ResourceUrlEncodingFilter` conditions which were inadvertently changed in commits64f04fceand6cc272ecand would back off if any `FilterRegistrationBean` was found. The updated conditions restores the behavior of Spring Boot 2.0.5 and allows users to directly register their own `ResourceUrlEncodingFilter` beans (as long as they don't use a `FilterRegistrationBean`). Fixes gh-14897