Unlike another poster, I do believe the risks of the virus are real; however reasonable precautions can help slow the spread. This would include keeping social distance and (at times) using a face mask. I use a basic non-medical mask (i.e. the "blue" ones) when I'm going into a place where distance is either hard to come by, or the mask is (loosely) required.
Having said that - I would not want someone coughing on me, but I guess it would also depend on circumstances. If the person coughed in my direction, say from a 'catch' in their throat, I would probably move, or suggest the other person keep their distance - yes, I have done that before
If it persisted, I would be less than polite about it. If I had an extra mask (which i might), I'd also offer it. Then I'd leave them to cough on someone else.