Execute tasks irrespective of default branch name

[ashmaroli]

Crossposting from https://github.com/jekyll/maintainers/issues/63#issuecomment-1100031133 for greater visibility:

Couple of issues encountered with jekyll/jekyll-avatar:

• JekyllBot doesn't update History.markdown automatically.
• JekyllBot doesn't create GitHub release automatically.

Context: The default branch at jekyll/jekyll-avatar is main instead of master

[parkr]

I just hit this with jekyll/github-metadata. There are a number of places we assume master instead of main.

[parkr]

Still works on repos with master: jekyll/teams#13

Works for main now too! jekyll/github-metadata#236

[ashmaroli]

Awesome! Thanks for addressing this @parkr