heroku architect: fix default git branch name

[thammegowda]

Closes #823

[JackUrb]

Hi @thammegowda, thanks for identifying and resolving this issue! Rather than forcing the master name though, could we force main and then also update the architect to reflect this decision?

[thammegowda]

welcome!
I thought of forcing main but I was not so sure if heroku supports deployment from main. I just found that it does!

So yes, we can force main instead of master. I will update the PR

[JackUrb]

Thanks for finding and fixing this issue!

[JackUrb]

Ah also could you resolve the black issues? I'll merge this in right after!

[thammegowda]

@JackUrb I tried fixing the issue. Please run the checks and let me know if it had fixed.
I havent used black before and if my recent commit hasn't fixed it, then give me a little bit more info about what the error is. Thanks!

[JackUrb]

Generally we manage running black through pre-commit. It's easy setup in case you choose to contribute in the future!