Global edit URL hardcodes master

[SamB]

This seems to be the offending line:

danger-plugin-spellcheck/src/index.ts

Line 233 in 2861b2e

const globalEditURL = repo && `/${repo.owner}/${repo.repo}/edit/master/${repo.path}`

I wouldn't have expected this to be an actual problem, except when I followed the link from microsoft/TypeScript-Website#1320 (comment) I got a 404 page.

Oh! It's a problem in that instance because there really is still a master branch lying around. Perhaps it ought to be renamed v1 ... still, might be a good idea to come up with a way for this plugin to actually link to the correct branch?

[orta]

edit urls have to have a branch reference like master, in theory we could use the GH api to check what the default branch is

[otherguy]

Now that GitHub defaults to main, this would make sense. We followed https://github.com/github/renaming and renamed all our master branches to main

[glensc]

I propose to use special HEAD instead. noticed this too when refactored in

• Add abstraction of repo provider #34