Adding automatic coverage

[florianjehn]

Would be nice to have a coverage badge that shows how much of our code is covered by the tests.
However, most solutions I found either don't work or require third party subscriptions services. If someone feels up to finding a good solution here I would very much appreciate it.

[florianjehn]

e.g. maybe this one: https://github.com/marketplace/actions/code-coverage-summary

[lukaszgajewski]

Maybe something like this https://coveralls.io/ ?
They say it's free for open source repos.

[florianjehn]

Haven't really looked into this further, as it is probably not worth the effort. But if you have an easy fix, feel free to submit a pull request.