But that's so weird because even if that's on the resume, any interviewer would be interested in know what the contribution was. Maybe revealing that you only "fixed typos" would do more harm than good?
Depends on your level of honesty. Given that you're fixing typos to say that you contributed to a project, you'd probably double down and quote the number of PR (remember to only do 1 typo fix per PR) and then add a real bug you may have fixed or make one up.
Unfortunately the entire interview process is why I usually try to hire former co-workers.