Add workflow for deploying to a staging website

[brandonpayton]

Motivation for the change, related issues

When making changes to the website deployment process and hosting code, we can reduce risk to production by testing with a staging environment first.

Implementation details

This PR modifies the production deployment script to take a workflow environment param that can be used to deploy to a different server via SSH. Then it adds a staging workflow to invoke the production workflow with a staging environment.

Testing Instructions (or ideally a Blueprint)

• Run the staging workflow and confirm it works
• Run the production workflow and confirm it still works

[brandonpayton]

I'm running into some issues with this and shouldn't spend more time on it for now. Let's close it and reopen later if needed.