Fix doc section anchor.

Author: OlgaMaciaszek

docs/modules/ROOT/pages/spring-cloud-openfeign.adoc

@@ -562,7 +562,7 @@ public interface UserClient extends UserService {
 
 WARNING: `@FeignClient` interfaces should not be shared between server and client and annotating `@FeignClient` interfaces with `@RequestMapping` on class level is no longer supported.
 
-[[feign-request/response-compression]]
+[[feign-request-response-compression]]
 === Feign request/response compression
 
 You may consider enabling the request or response GZIP compression for your