Could we have a staging deployment of the dashboard

[surchs]

When reviewing dashboard PRs it would be nice to have an easy way to look at the running app as it would look like merged, and like we do for our static apps. I know dash is a bit trickier to deploy, but I wonder if we could use any of the free tiers out there to have it auto-deploy and paste a link into the PR.

E.g.

• https://aws.amazon.com/free/webapps/?p=ft&z=subnav&loc=3
• https://cloud.google.com/free/docs/free-cloud-features#app-engine
• https://www.pythonanywhere.com/pricing/
  or even
• on openstack using our own server (probably more involved to handle the webhooks etc)

[github-actions]

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