Fix ATS documentation about docs HOT 3 CLOSED

I'll try to fix this, but there are some error messages I don't understand.
Looking at the first two lines:
./_site/ATS/ATS+Core+Actions/Assert+Equals.html internally linking to /ATS/ATS+Core+Actions/, which does not exist (line 110)
There's no link on this page. How can I fix it?

from docs.

That's a good one, didn't notice it yet. I will first investigate this further down the week

from docs.

I fixed this in development. The problem is that it uses subfolders, which are not compatible with our menu template right now. That's why it says that it's linking.

I fixed this by adding index.md files to these folders. Now all the links are working and checked. Closing the referenced branch as well as this is not necessary anymore

from docs.