Add GH action to check for email addresses in issues and comments

[seisvelas]

Last time when I updated every repo to use the new version, I did so manually via the GitHub interface. But then it turned out I forgot some.

So, this time I decided to be lazy and write a little script to check all of them. Here was the output:

➜  Code python3 emails_updated.py
error checking repo fine-uploader, status code 404
fine-uploader does not have the new action

As far as I can tell, this is the only repo still missing the action. Therefore, I'm adding it!

Next time I update it, I'll also make sure to write a script to push the change to every repo and open a PR.