Remove old Known Issue
Remove old Known Issue

It's resolved according to @lukipuki, see:

https://github.com/Tarrasch/problemtools/commit/b1e6641a80f3f42a26a15c67b385d39d591e5e1b#commitcomment-8588216

Kattis/problemtools,jsannemo/problemtools,jbransen/problemtools,godmar/problemtools,ghamerly/problemtools,jsannemo/problemtools,ghamerly/problemtools,ghamerly/problemtools,jbransen/problemtools,Kattis/problemtools,jbransen/problemtools,Kattis/problemtools,godmar/problemtools,ghamerly/problemtools,jsannemo/problemtools,jbransen/problemtools,godmar/problemtools,jsannemo/problemtools,Kattis/problemtools,godmar/problemtools