Newly generated file not included in commit about ghaction-github-pages

[enyo]

I've realised that there seems to be another problem with generating this file. I also can't copy it so it is not related to this library.

[enyo]

I've spent a few hours debugging this now, and it's actually quite funny. I had a .gitignore file in my project, that prevented .index.md from being committed, since it's supposed to be generated.
But since this script actually takes the whole folder and creates a commit, it also takes the .gitignore file into account! So I made sure to delete the .gitignore file before invoking the github pages action... but it still wasn't working!
After quite some time of debugging, I realised, that I had keep_history set to true, and that meant that it always pulled the files from the gh-pages branch (which already included the .gitignore file, and prevented the index.md file from being committed.

Just thought I'd share this, since others might run into a similar problem.

@crazy-max do you think it's worth mentioning something about .gitignore files in your README?