At present, both Spring MVC and Spring WebFlux auto-configurations
hardcode the path pattern for WebJars resource handlers to
"/webjars/**", which means users are unable to change the path.
This commit introduces "spring.mvc.webjars-path-pattern" and
"spring.webflux.webjars-path-pattern" configuration properties that
allow customization of WebJars resource handler path pattern.
See gh-31769
Vedran Pavic
Andy Wilkinson
Moritz Halbritter
Phillip Webb
Madhura Bhave