Change branch from "master" to "main"

[kersten1]

As a gentle reminder, the "Friendly Terminology" policy link which uses the "Inclusive Naming" community link includes the word "master" as a Tier 1: Replace Immediately word.

You can follow these steps to rename your branch: https://gist.github.com/danieldogeanu/739f88ea5312aaa23180e162e3ae89ab