Use Docker for development, publishing and easier scaling

[olemp]

Discussed in #875

^{Originally posted by olemp November 5, 2020}

• I have searched for existing issues to avoid creating duplicates

TLDR

We should look into using Docker for development, publishing and easier scaling.

Description

Our Linux Web App didapp is already using Docker to run our app, so it makes sense to also use Docker locally, when testing locally and in the CI. We can select Docker image for publish option for new apps, perhaps for existing ones aswell?