Investigate code coverage within pytest

[TheCodeSummoner]

As in the title, we want to measure code coverage. Possibly display the statistics about tests passed + coverage on github too (I know there are tools to do that).

[ConnorH2525]

Requires a plugin called pytest-cov which shows the statistics about tests passed. A coverage config file can also help get more control over how it works. However I could not find anything about it linking to github and it doesn't seem to have support for python 3.8 at the minute.

[TheCodeSummoner]

Can we see some examples please?

[ConnorH2525]

Have added how to generate coverage report to README in tests. Still working on integration with GitHub. The pytest-cov I mentioned previously provides some more functionality but I don't think it will be useful for us.