Use new Google Cloud Storage package for managing storage objects

[aaronsky]

Note from the module used for the GCS Storage API package used by the agent:

import "google.golang.org/api/storage/v1"

Package storage provides access to the Cloud Storage JSON API.

This package is DEPRECATED. Use package cloud.google.com/go/storage instead.

Reporting this only because I couldn't find another issue for this, and as they say, "see something say something."

[jayco]

Good pick up, thanks for letting us know @aaronsky!