[Feature request] Create a Code of Conduct on GitHub

[L1lith]

Is your feature request related to a problem? Please describe. A code of conduct is kinda like the rules for contributing. I think this would be a good thing to have :) For example here's the code of conduct from astro-18next, they're pretty good.

Describe the solution you'd like We need to add a Code of Conduct so that it shows up on the side bar on the right, by changing the settings in GitHub