Add pre-deploy job to ucam-faas module

Adds a pre-deploy job mirroring functionality in the gcp-cloud-run module.

I was under the impression that this module actually used our cloud run module under the hood - but looks like it actually does not. This change therefore mirrors the gcp-cloud-run module's functionality. It's frustrating having to copy the code over, but I don't see any other way to mirror this functionality unless we span the pre-deploy job out into its own module.

Part of #7 (closed)