Avoid repeated respond_to? calls in Commissioner
Avoid repeated respond_to? calls in Commissioner

A profile showed `#respond_to?` calls taking more than 10% of RC's run time.
The vast majority of these calls were occurring in `Commissioner`.

Although `#respond_to?` is not slow, calling for every combination of cop and
AST node meant tens of millions of calls would be made on any sizeable codebase.

This approximately halves the number of `#respond_to?` calls made. We still need
to reduce further.

akihiro17/rubocop,tdeo/rubocop,bankair/rubocop,akihiro17/rubocop,alexcstark/rubocop,bquorning/rubocop,sinsoku/rubocop,volkert/rubocop,iGEL/rubocop,backus/rubocop,NobodysNightmare/rubocop,jmks/rubocop,deivid-rodriguez/rubocop,lucasuyezu/rubocop,alexdowad/rubocop,mikegee/rubocop,legendetm/rubocop,meganemura/rubocop,sinsoku/rubocop,panthomakos/rubocop,haziqhafizuddin/rubocop,Drenmi/rubocop,lucasuyezu/rubocop,sue445/rubocop,sue445/rubocop,mclark/rubocop,volkert/rubocop,pocke/rubocop,urbanautomaton/rubocop,bbatsov/rubocop,NobodysNightmare/rubocop,vergenzt/rubocop,alexcstark/rubocop,petehamilton/rubocop,smakagon/rubocop,rrosenblum/rubocop,deivid-rodriguez/rubocop,jfelchner/rubocop,panthomakos/rubocop,tdeo/rubocop,palkan/rubocop,petehamilton/rubocop,dreyks/rubocop,panthomakos/rubocop,scottmatthewman/rubocop,maxjacobson/rubocop,hanumakanthvvn/rubocop,lumeet/rubocop,pocke/rubocop,meganemura/rubocop,alexdowad/rubocop,bankair/rubocop,backus/rubocop,melch/rubocop,bbatsov/rubocop,hanumakanthvvn/rubocop,ilansh/rubocop,savef/rubocop,palkan/rubocop,lumeet/rubocop,melch/rubocop,jmks/rubocop,haziqhafizuddin/rubocop,tejasbubane/rubocop,mikegee/rubocop,jfelchner/rubocop,vergenzt/rubocop,rrosenblum/rubocop,ilansh/rubocop,tejasbubane/rubocop,palkan/rubocop,rrosenblum/rubocop,maxjacobson/rubocop,mikegee/rubocop,b-t-g/rubocop,sue445/rubocop,scottmatthewman/rubocop,iGEL/rubocop,meganemura/rubocop,legendetm/rubocop,b-t-g/rubocop,savef/rubocop,smakagon/rubocop,rtlechow/rubocop,deivid-rodriguez/rubocop,jmks/rubocop,rtlechow/rubocop,tejasbubane/rubocop,urbanautomaton/rubocop,petehamilton/rubocop,bquorning/rubocop,bquorning/rubocop,jfelchner/rubocop,vergenzt/rubocop,mclark/rubocop,tdeo/rubocop,dreyks/rubocop,akihiro17/rubocop,maxjacobson/rubocop,Drenmi/rubocop