RemoveJsonAttributesResponseBody filter does not exists in WebMVC context : remove it from documentation or implement it

[lassellea-sfeir]

Describe the bug
Hi,
when we read Spring Gateway documentation, we can think that RemoveJsonAttributesResponseBody can be used in WebMVC context :

• https://docs.spring.io/spring-cloud-gateway/reference/spring-cloud-gateway-server-webmvc/filters/removejsonattributesresponsebody.html
• https://github.com/spring-cloud/spring-cloud-gateway/blob/main/docs/modules/ROOT/pages/spring-cloud-gateway-server-webmvc/filters/removejsonattributesresponsebody.adoc#removejsonattributesresponsebody-filter

But in fact, this filter does not exist in WebMVC context :

Caused by: java.lang.IllegalArgumentException: Unable to find operation interface org.springframework.web.servlet.function.HandlerFilterFunction for removeJsonAttributesResponseBody with args {_genkey_0=myjsonattribute}

No RemoveJsonAttributesResponseBody class found in sources : https://github.com/spring-cloud/spring-cloud-gateway/tree/main/spring-cloud-gateway-server-webmvc/src/main/java/org/springframework/cloud/gateway/server/mvc/filter

-> Please update documentation or implement this filter : it is very important, because we are doing design based on documentation