Fix outdated comment

ConflictSet.cpp

@@ -125,7 +125,7 @@ struct BitSet {
   void reset(int i);
   int firstSetGeq(int i) const;
 
-  // Calls `f` with the index of each bit set in [begin, end)
+  // Calls `f` with the index of each bit set
   template <class F> void forEachSet(F f) const {
     // See section 3.1 in https://arxiv.org/pdf/1709.07821.pdf for details about
     // this approach