Add a CI job for automatic deployments when pushing to develop and master

[M4GNV5]

Currently after pushing to the corresponding branches we have to manually log into the server and deploy the changes by running docer-compose up. Since only @alexhorn and me have access to the server other contributors cannot have their changes deployed.

We could set up a CI pipeline which automatically runs docker-compose up -d --build on our server after a push to develop and master. From my experience, the best way is to generate a ssh key for github and limit the commands that can be executed using this ssh key using the command=... option in the authorized_keys file.

[shei99]

A different solution to this would be to:

• Build the Docker Image in the CI/CD Pipeline
• Push the newly built image to a registry (GitHub, Dockerhub or self hosted)
• Use Watchtower (https://containrrr.dev/watchtower/) to update the image on the server

Additionally, all the docker-compose files should be versioned in a separate repository.