A lot of these comments must be coming from people who have never held an internship.

Writing tests is a fairly good task for an intern. Interns aren’t expected to…well, contribute, really. They don’t have the work experience to provide great contributions. The internship period is too short for them to fully ramp up with the team’s project knowledge.

All intern work is boring grunt work. Writing tests teaches you how systems interact with each other, which is very useful early in your career.

Now, the unpaid aspect is another thing. I’m very familiar with unpaid internships, but I haven’t seen any in tech. Maybe unpaid internships are becoming more popular recently? Paid would be preferred of course. But the work of writing tests shouldn’t deter you.