Add WebFlux AutoConfiguration support for spring-security-oauth2-resource-server #13948
Description
Similar to #13787 but for WebFlux. We should support configuring the jwk set uri in Spring Boot (no need at this point to support the public key). You can find a sample in https://github.com/spring-projects/spring-security/blob/master/samples/boot/oauth2resourceserver-webflux/