02 Problem Solving / Optional readings link does not open

[azs6189]

At the bottom of the Learning at Ada: 02 Problem Solving page, there is a section 'Optional readings'. The link What Is a Good Test Case? (Cem Kaner, J.D., Ph.D.) on the page no longer seems to work and could probably be updated to the link below.

https://profinit.eu/wp-content/uploads/2016/03/WhatIsGoodTestcase.pdf

[LaurenC2022]

Pull request #275 is made to fix this issue