code: public CompletableFuture<Pair<List<String>, String>> listStreams(final String scope, final String token, final int limit) {
          Exceptions.checkNotNullOrEmpty(scope, "scope");
          return streamStore.listStream(scope, token, limit, executor);
      }
docs: List existing streams in scopes.
  
  @param scope Name of the scope.
  @param token continuation token
  @param limit limit for number of streams to return.
  @return List of streams in scope.