Also support "main" as default branch for repo normalization #48
Description
Describe the bug
Master-slave is an oppressive metaphor that will and should never become fully detached from history. Aside from being unprofessional and oppressive it stifles participation
(1.1. Master-slave - Terminology, Power and Oppressive Language)
Expected behavior
The normalize_repos/normalize_repos.py script should be updated to support both main and master as the primary branch.