Update flask to 1.0.3

[pyup-bot]

This PR updates Flask from 1.0.2 to 1.0.3.

Changelog

1.0.3

-------------

Unreleased

-   :func:`send_file` encodes filenames as ASCII instead of Latin-1
 (ISO-8859-1). This fixes compatibility with Gunicorn, which is
 stricter about header encodings than PEP 3333. (`2766`_)
-   Allow custom CLIs using ``FlaskGroup`` to set the debug flag without
 it always being overwritten based on environment variables.
 (`2765`_)
-   ``flask --version`` outputs Werkzeug's version and simplifies the
 Python version. (`2825`_)
-   :func:`send_file` handles an ``attachment_filename`` that is a
 native Python 2 string (bytes) with UTF-8 coded bytes. (`2933`_)
-   A catch-all error handler registered for ``HTTPException`` will not
 handle ``RoutingException``, which is used internally during
 routing. This fixes the unexpected behavior that had been introduced
 in 1.0. (`2986`_)

.. _2766: https://github.com/pallets/flask/issues/2766
.. _2765: https://github.com/pallets/flask/pull/2765
.. _2825: https://github.com/pallets/flask/pull/2825
.. _2933: https://github.com/pallets/flask/issues/2933
.. _2986: https://github.com/pallets/flask/pull/2986

Links

• PyPI: https://pypi.org/project/flask
• Changelog: https://pyup.io/changelogs/flask/
• Homepage: https://www.palletsprojects.com/p/flask/

[pyup-bot]

Closing this in favor of #458