migrate from using gsutil to using gcloud storage #3
Description
The gcloud storage CLI has appreciably better performance than gsutil. The two commands are otherwise very similar in invocation, with minor differences in compatibility. A shim exists to use gcloud storage in place of gsutil in scripts (via changes to the .boto config or by setting gsutil -o "GSUtil:use_gcloud_storage=True"). The shim page also notes differences in behavior between the two commands.
If the gsutil commands currently being used in the incremental upload script have behavior parity with those available via gcloud storage, we should switch to gcloud storage to take advantage of the performance improvements (ideally by making actual changes and not relying on the shim, especially since rsync is not currently supported by the shim, but gcloud storage proper has it).