Fix: Add a validation on the monorepo path - warn if it ends with docs.json

[ky-zo]

I was lazy and didn't read and specified path to the file, not to the folder.
Couldn't figure out why it doesn't work.

If there was a client-side validation that checks if path ends with .json and would show warning "specify the path to the folder", that'd be cool.

would cut my confusion by 12minutes