Apply suggestions from code review

Co-authored-by: Martin Durant <[email protected]>

Author: alanhdu

fsspec/caching.py

@@ -144,7 +144,7 @@ def __getstate__(self) -> dict[str, Any]:
         del state["cache"]
         return state
 
-    def __setstate__(self, state) -> None:
+    def __setstate__(self, state: dict[str, Any]) -> None:
         # Restore instance attributes
         self.__dict__.update(state)
         self.cache = self._makefile()
@@ -277,7 +277,7 @@ def __getstate__(self) -> dict[str, Any]:
         del state["_fetch_block_cached"]
         return state
 
-    def __setstate__(self, state) -> None:
+    def __setstate__(self, state: dict[str, Any]) -> None:
         self.__dict__.update(state)
         self._fetch_block_cached = functools.lru_cache(state["maxblocks"])(
             self._fetch_block