Remove incorrect comment

mock.py

@@ -175,7 +175,6 @@ def _getsignature(func, skipfirst, instance=False):
         regargs, varargs, varkw, defaults, kwonly, kwonlydef, ann = argspec
     else:
         try:
-            # not using annotations
             regargs, varargs, varkwargs, defaults = inspect.getargspec(func)
         except TypeError:
             # C function / method, possibly inherited object().__init__