Method references `Async::await` are not taken away

The instrumentation tool takes away all `Async.await` occurrences, but does not take away `Async::await`. I think this is a bug?

E.g.
```java
final List<CompletableFuture<Void>> futures = new ArrayList<>();
futures.add(CompletableFuture.completedFuture(null));
futures.stream().map(Async::await).collect(Collectors.toList());
```
The `Async::await` stays after instrumentation.