Add CI to push to DockerHub

[qwelyt]

As there now is a Dockerfile that can be built, create a CI-action to automagically build and push to dockerhub when a release is made and when things are merged into main

• Action to always build latest on updates to main
• Action to tag containers with release versions (like 0.2.3 etc)

This makes takes away the manual process of updating the DockerHub image.

[roipoussiere]

I agree with the idea, but with some additional suggestions:

when things are merged into main

The action should be triggered only when a tagged commit is pushed on main, this way the built version will be more stable. Because typically bugs appears on main and fixed before publishing a new release. I don't have yet a test suite to check the project stability before each push on main, I only do functional tests manually.

The action could also publish the project on PyPI.

And obviously docker hub and pypi credentials will be stored in environment variables.

Would you like to work on this?

[roipoussiere]

Note that this repository is mirrored with https://framagit.org/roipoussiere/cadquery-server and CI could eventually be performed here, using a .gitlab-ci.yml.

[roipoussiere]

PR merged: #42

But CI failed: https://github.com/roipoussiere/cadquery-server/actions/runs/3070866018/jobs/4961023286

[roipoussiere]

fixed in 5234ffd and 48f48a8 thanks for your contribution @qwelyt :)