Fix integration/advent2011-day23.t
Fix integration/advent2011-day23.t

no idea why a Bag was used here before, a set seems to work fine
(and does not rely on now-deprecated, implicit coercions)

laben/roast,skids/roast,laben/roast,perl6/roast,skids/roast,cygx/roast,dankogai/roast,niner/roast,b2gills/roast,dankogai/roast,bitrauser/roast,b2gills/roast,dankogai/roast,zostay/roast,skids/roast,cygx/roast,laben/roast,niner/roast,dogbert17/roast,cygx/roast,dogbert17/roast,bitrauser/roast,niner/roast,zostay/roast,b2gills/roast,zostay/roast