Add tests to exercise some previously unexercised lines:

• _SpecialGenericAlias.__setattr__() for non-dunder, non-"allowed" attributes (src)
• Wrong number of type arguments given to a _SpecialGenericAlias from without defaults (src)
• Attempting to specialize a _SpecialGenericAlias with 0 type parameters (src)
• Setting <thing>.__module__ on Python implementations that don't supply sys._getframemodulename or sys._getframe (src)
• Calling get_type_hints() with types.GenericAlias (src)
• Exception raised by __init_subclass__() of ParamSpec (src)
• The methods __or__() and __ror__() of _SpecialForm (src)
• The methods __repr__ and __reduce__ of NoExtraItems (test case copied from NoDefaultTests) (src)