anchor.diff:  import javax.ws.rs.Path;
   import javax.ws.rs.QueryParam;
   import java.util.Set;
  -import java.util.concurrent.CompletionStage;
   
   @Path("/extensions")
   @RegisterRestClient
  
positive.code: [source, java]
  ----
  package org.acme.rest.client;
  
  import org.eclipse.microprofile.rest.client.ext.ClientHeadersFactory;
  
  
negative.code: ----
  package org.acme.rest.client;
  
  import io.smallrye.mutiny.Uni;
  import org.eclipse.microprofile.rest.client.inject.RestClient;
  
  import javax.ws.rs.GET;
  import javax.ws.rs.Path;
  import java.util.Set;
  
  @Path("/extension")
  public class ExtensionsResource {
  