Update Default branch name

[ultamatt]

node-pre-gyp-github/index.js

Line 66 in 5a99394

'target_commitish': 'master',

Hey! Thanks for this code. I'm working on using it along with the neon publish tutorial. It's not really working for me because of this default branch name stuff here. I can make a PR for this in a bit, but it would be nice if:

1. We change this from 'master' to 'main'
2. Perhaps later we could offer this field to be overloaded by the 'binary' in package.json.

Thanks! I'll maybe PR this if I can later tonight.

[daniellockyer]

Would love to see a PR 🙂

[ultamatt]

#44