fix stubtest issue post-merge

Author: davidhewitt

.github/workflows/ci.yml

@@ -194,7 +194,6 @@ jobs:
         if: steps.cache-py.outputs.cache-hit != 'true'
 
       - run: pip install .
-        if: steps.cache-py.outputs.cache-hit != 'true'
 
       - run: pip freeze
 

python/pydantic_core/_pydantic_core.pyi

@@ -51,7 +51,7 @@ class Some(Generic[_T]):
     @property
     def value(self) -> _T: ...
     @classmethod
-    def __class_getitem__(cls, item: Any) -> Type[Self]: ...
+    def __class_getitem__(cls, item: Any, /) -> Type[Self]: ...
 
 @final
 class SchemaValidator: