Use PEP 585 syntax wherever possible (#6717)

stubs/oauthlib/oauthlib/common.pyi

@@ -1,4 +1,4 @@
-from typing import Any, Dict
+from typing import Any
 
 UNICODE_ASCII_CHARACTER_SET: str
 CLIENT_ID_CHARACTER_SET: str
@@ -28,7 +28,7 @@ def add_params_to_uri(uri, params, fragment: bool = ...): ...
 def safe_string_equals(a, b): ...
 def to_unicode(data, encoding: str = ...): ...
 
-class CaseInsensitiveDict(Dict[Any, Any]):
+class CaseInsensitiveDict(dict[Any, Any]):
     proxy: Any
     def __init__(self, data) -> None: ...
     def __contains__(self, k): ...

stubs/oauthlib/oauthlib/oauth2/rfc6749/tokens.pyi

@@ -1,6 +1,6 @@
-from typing import Any, Dict
+from typing import Any
 
-class OAuth2Token(Dict[Any, Any]):
+class OAuth2Token(dict[Any, Any]):
     def __init__(self, params, old_scope: Any | None = ...) -> None: ...
     @property
     def scope_changed(self): ...