Fix git init to main branch in generate/_project.py

[shanilpanara]

After running the commands

pip install softnanotools
cd /tmp
softnanotools.generate project example --pre-commit --pip-install

I get the following output

[shanilpanara]

I've found the issue: git init -b main only works in git versions 2.28 or later, I have 2.25.1

[shanilpanara]

Easy solution:

git init # default branch is named to master < 2.28 and main >= 2.28
git branch -M main # rename default brain to main regardless of the previous default branch name!