Remove a few unused TypedDicts (#8522)

stubs/chardet/chardet/__init__.pyi

@@ -8,7 +8,8 @@ if sys.version_info >= (3, 8):
 else:
     from typing_extensions import TypedDict
 
-class _LangModelType(TypedDict):
+# unused in this module, but imported in multiple submodules
+class _LangModelType(TypedDict):  # noqa: Y049
     char_to_order_map: tuple[int, ...]
     precedence_matrix: tuple[int, ...]
     typical_positive_ratio: float
@@ -16,12 +17,5 @@ class _LangModelType(TypedDict):
     charset_name: str
     language: str
 
-class _SMModelType(TypedDict):
-    class_table: tuple[int, ...]
-    class_factor: int
-    state_table: tuple[int, ...]
-    char_len_table: tuple[int, ...]
-    name: str
-
 def detect(byte_str: bytes | bytearray) -> _FinalResultType: ...
 def detect_all(byte_str: bytes | bytearray, ignore_threshold: bool = ...) -> list[_IntermediateResultType]: ...