Log Message:
py-flask: update to 3.0.0.

Version 3.0.0
-------------

Released 2023-09-30

-   Remove previously deprecated code. :pr:`5223`
-   Deprecate the ``__version__`` attribute. Use feature detection, or
    ``importlib.metadata.version("flask")``, instead. :issue:`5230`
-   Restructure the code such that the Flask (app) and Blueprint
    classes have Sans-IO bases. :pr:`5127`
-   Allow self as an argument to url_for. :pr:`5264`
-   Require Werkzeug >= 3.0.0.