getAsyncK<T extends Object>  method 
Retrieves an asynchronous dependency.
Implementation
@pragma('vm:prefer-inline')
Option<Async<T>> getAsyncK<T extends Object>(
  Entity typeEntity, {
  Entity groupEntity = const DefaultEntity(),
  bool traverse = true,
}) {
  return getK<T>(
    typeEntity,
    groupEntity: groupEntity,
    traverse: traverse,
  ).map((e) => e.toAsync());
}