remove no-cover

Author: HalfWhitt

core/src/toga/style/pack.py

@@ -121,8 +121,7 @@ def __get__(self, obj, objtype=None):
         return super().__get__(obj)
 
     def __set__(self, obj, value):
-        # This won't be executed until @dataclass is added
-        if value is self:  # pragma: no cover
+        if value is self:
             # This happens during autogenerated dataclass __init__ when no value is
             # supplied.
             return