Set type of default django.core.cache.cache to BaseCache (#998)

* Set type of default `django.core.cache` to `BaseCache`

- The previous type `ConnectionProxy` is just a proxy class, thus
  revealing `Any` for _all_ cache methods

* fixup! Set type of default `django.core.cache` to `BaseCache`

django-stubs/core/cache/__init__.pyi

@@ -16,5 +16,5 @@ class CacheHandler(BaseConnectionHandler):
 
 def close_caches(**kwargs: Any) -> None: ...
 
-cache: ConnectionProxy
+cache: BaseCache
 caches: CacheHandler

django-stubs/core/cache/backends/base.pyi

@@ -12,28 +12,30 @@ def default_key_func(key: Any, key_prefix: str, version: Any) -> str: ...
 def get_key_func(key_func: Optional[Union[Callable, str]]) -> Callable: ...
 
 class BaseCache:
-    default_timeout: int = ...
+    default_timeout: Optional[int] = ...
     key_prefix: str = ...
     version: int = ...
     key_func: Callable = ...
     def __init__(self, params: Dict[str, Any]) -> None: ...
-    def get_backend_timeout(self, timeout: Any = ...) -> Optional[float]: ...
-    def make_key(self, key: Any, version: Optional[Any] = ...) -> str: ...
-    def add(self, key: Any, value: Any, timeout: Any = ..., version: Optional[Any] = ...) -> bool: ...
-    def get(self, key: Any, default: Optional[Any] = ..., version: Optional[Any] = ...) -> Any: ...
-    def set(self, key: Any, value: Any, timeout: Any = ..., version: Optional[Any] = ...) -> None: ...
-    def touch(self, key: Any, timeout: Any = ..., version: Optional[Any] = ...) -> bool: ...
-    def delete(self, key: Any, version: Optional[Any] = ...) -> None: ...
+    def get_backend_timeout(self, timeout: Optional[int] = ...) -> Optional[float]: ...
+    def make_key(self, key: Any, version: Optional[int] = ...) -> str: ...
+    def add(self, key: Any, value: Any, timeout: Optional[int] = ..., version: Optional[int] = ...) -> bool: ...
+    def get(self, key: Any, default: Optional[Any] = ..., version: Optional[int] = ...) -> Any: ...
+    def set(self, key: Any, value: Any, timeout: Optional[int] = ..., version: Optional[int] = ...) -> None: ...
+    def touch(self, key: Any, timeout: Optional[int] = ..., version: Optional[int] = ...) -> bool: ...
+    def delete(self, key: Any, version: Optional[int] = ...) -> None: ...
     def get_many(self, keys: Iterable[Any], version: Optional[int] = ...) -> Dict[Any, Any]: ...
     def get_or_set(
-        self, key: Any, default: Optional[Any], timeout: Any = ..., version: Optional[int] = ...
+        self, key: Any, default: Optional[Any], timeout: Optional[int] = ..., version: Optional[int] = ...
     ) -> Optional[Any]: ...
-    def has_key(self, key: Any, version: Optional[Any] = ...) -> bool: ...
+    def has_key(self, key: Any, version: Optional[int] = ...) -> bool: ...
     def incr(self, key: Any, delta: int = ..., version: Optional[int] = ...) -> int: ...
     def decr(self, key: Any, delta: int = ..., version: Optional[int] = ...) -> int: ...
     def __contains__(self, key: Any) -> bool: ...
-    def set_many(self, data: Dict[Any, Any], timeout: Any = ..., version: Optional[Any] = ...) -> List[Any]: ...
-    def delete_many(self, keys: Iterable[Any], version: Optional[Any] = ...) -> None: ...
+    def set_many(
+        self, data: Dict[Any, Any], timeout: Optional[int] = ..., version: Optional[int] = ...
+    ) -> List[Any]: ...
+    def delete_many(self, keys: Iterable[Any], version: Optional[int] = ...) -> None: ...
     def clear(self) -> None: ...
     def validate_key(self, key: Any) -> None: ...
     def incr_version(self, key: Any, delta: int = ..., version: Optional[int] = ...) -> int: ...