Run pyupgrade on all other python sources (#13375)

Author: sobolevn

misc/proper_plugin.py

@@ -1,5 +1,4 @@
-from typing import Callable, Optional
-from typing_extensions import Type as typing_Type
+from typing import Callable, Optional, Type as typing_Type
 
 from mypy.nodes import TypeInfo
 from mypy.plugin import FunctionContext, Plugin

test-data/unit/plugins/decimal_to_int.py

@@ -1,4 +1,3 @@
-
 from mypy.plugin import Plugin