Test that other required Git ignores present

[karlhorky]

Test that other required Git ignore files / folders are:

1. present in .gitignore
2. not present in Git

Like the node_modules check we already have

Check the https://github.com/upleveled/next-js-example-fall-2022/ repo for more

eg. the playwright/reports directory, preventing this issue of a student's GitHub repo being reported as "mostly HTML":

I had that as well. I guess you have a file in your playwright/report folder that is not ignored. because that apparently is a huge file with only html.
so I deleted it, checked my .gitignore file if it really is ignored and ran playwright again to check if it still works. afterwards the bar changed to the mostly TS