Bump version to 0.3.3

Author: cdce8p

python_typing_update/const.py

@@ -7,7 +7,7 @@
 from typing import NamedTuple
 
 version = (0, 3, 3)
-dev_version = 1  # Set to `None` for release
+dev_version = None  # Set to `None` for release
 
 version_str = '.'.join(map(str, version))
 if dev_version is not None: