Updated counter_pprint to use most_common() rather than sorted()

IPython/lib/pretty.py

@@ -918,7 +918,7 b' def _counter_pprint(obj, p, cycle):'
     if cycle:
         p.pretty(cls_ctor(RawText("...")))
     elif len(obj):
-        p.pretty(cls_ctor(dict(sorted(obj.items(), key=lambda x: x[1], reverse=True))))
+        p.pretty(cls_ctor(dict(obj.most_common())))
     else:
         p.pretty(cls_ctor())