Implement a listObjects() function inside connection class for google cloud provider. The behaviour is that the function lists all of the objects on the bucket. The SDK should utilise the listObject function from the GCP SDK. Once implemented the developer will also need to test this functionality via python testing and unit testing.

reference: https://cloud.google.com/storage/docs/listing-objects#client-libraries

Definition of Done
ListObject function is completed with added unit test and python testing.