code: public void delete(String personGroupId, UUID personId) {
          deleteWithServiceResponseAsync(personGroupId, personId).toBlocking().single().body();
      }
docs: Delete an existing person from a person group. Persisted face images of the person will also be deleted.
  
  @param personGroupId Id referencing a particular person group.
  @param personId Id referencing a particular person.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws APIErrorException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent