make class public to appease javadoc

Author: laurit

instrumentation/spring/spring-webflux/spring-webflux-5.3/testing-webflux7/src/main/java/io/opentelemetry/instrumentation/spring/webflux/client/Webflux7Util.java

@@ -11,7 +11,7 @@
 import org.springframework.web.reactive.function.client.WebClient;
 import reactor.core.publisher.Mono;
 
-class Webflux7Util {
+public class Webflux7Util {
   static final boolean isWebflux7 = detectWebflux7();
 
   private static boolean detectWebflux7() {