removes RUBYOPT env before calling judge scripts
removes RUBYOPT env before calling judge scripts

nattee/cafe-grader-judge-scripts,nattee/cafe-grader-judge-scripts,jittat/cafe-grader-judge-scripts,nattee/cafe-grader-judge-scripts,jittat/cafe-grader-judge-scripts,nattee/cafe-grader-judge-scripts,jittat/cafe-grader-judge-scripts,nattee/cafe-grader-judge-scripts,jittat/cafe-grader-judge-scripts