Use Python 3.8 instead of 3.6 as environment Python version

[felixfontein]

Setup Python 3.6 on ubuntu-latest no longer works since ubuntu-latest == ubuntu-22.04. See actions/setup-python#544.

[webknjaz]

@felixfontein why do you add so many trailing periods to Git commit titles? A typical convention is not to do that, I have never seen this trailing-dot style before.

[felixfontein]

@webknjaz I think commit messages should consist of proper sentences, and these tend to end with periods.

[webknjaz]

@felixfontein looks like you're confusing commit message titles (which is what is displayed if you tell git log to hide most content) with full commit descriptions. Titles shouldn't contain a trailing period (this is one of the things that linters like gitlint check for).

Here's how the Git developers themselves write the commit messages + rationale: https://gist.github.com/webknjaz/cb7d7bf62c3dda4b1342d639d0e78d79.

[felixfontein]

@webknjaz I don't think I'm confusing that, I'm mainly having a different opinion.

[webknjaz]

I see. FWIW I've been experimenting with integrating gitlint in some of the other projects I have for a while now and will soon do that across the board because it's important to keep good Git history.