Use abbreviated expression lambda instead of statement lambda

Closes gh-1126

spring-web/src/main/java/org/springframework/http/server/reactive/RxNettyServerHttpResponse.java

@@ -82,11 +82,9 @@ public class RxNettyServerHttpResponse extends AbstractServerHttpResponse {
 	protected Mono<Void> writeAndFlushWithInternal(
 			Publisher<Publisher<DataBuffer>> body) {
 		Flux<ByteBuf> bodyWithFlushSignals = Flux.from(body).
-				flatMap(publisher -> {
+				flatMap(publisher -> Flux.from(publisher).
-					return Flux.from(publisher).
 						map(NettyDataBufferFactory::toByteBuf).
-							concatWith(Mono.just(FLUSH_SIGNAL));
+						concatWith(Mono.just(FLUSH_SIGNAL)));
-				});
 		Observable<ByteBuf> content = RxJava1Adapter.publisherToObservable(bodyWithFlushSignals);
 		ResponseContentWriter<ByteBuf> writer = this.response.write(content, bb -> bb == FLUSH_SIGNAL);
 		return RxJava1Adapter.observableToFlux(writer).then();