SolrJ async admin request helpers don't work with per-request based authentication

Discovered this set of related bugs while trying to write a test using BasicAuth...

• AsyncCollectionAdminRequest.processAndWait(...) doesn't copy any authentication settings (example: if the user called: setBasicAuthCredentials(...) ) from the original AsyncCollectionAdminRequest when creating the underlying RequestStatus instance
• Even if clients create their own RequestStatus instance and set credentials on it before calling waitFor(...), it doesn't copy those credentials when trying to call deleteAsyncId(...) on COMPLETED or FAILED results