Fixes CI

Author: sobolevn

docs/pages/concept.rst

@@ -129,11 +129,11 @@ function signatures and return types in all cases:
   ... def example(instance) -> str:
   ...     return 'default'
   ...
-  >>> @example.register
+  >>> @example.register(int)
   ... def _example_int(instance: int, other: int) -> int:
   ...     return instance + other
   ...
-  >>> @example.register
+  >>> @example.register(str)
   ... def _example_str(instance: str) -> bool:
   ...     return bool(instance)
   ...

docs/pages/typesafety.rst

@@ -82,7 +82,7 @@ So, this would not work:
   ...
   Traceback (most recent call last):
   ...
-  TypeError: Subscripted generics cannot be used with class and instance checks
+  TypeError: ...
 
 
 But, this will (note that we use ``list`` inside ``.instance()`` call):