Update python-telegram-bot to 13.15

[pyup-bot]

This PR updates python-telegram-bot from 13.9 to 13.15.

Changelog

13.11

=============
*Released 2022-02-02*

This is the technical changelog for version 13.11. More elaborate release notes can be found in the news channel `pythontelegrambotchannel <https://t.me/pythontelegrambotchannel>`_.

**Major Changes:**

- Full Support for Bot API 5.7 (`2881`_)

.. _`2881`: https://github.com/python-telegram-bot/python-telegram-bot/pull/2881

13.10

=============
*Released 2022-01-03*

This is the technical changelog for version 13.10. More elaborate release notes can be found in the news channel `pythontelegrambotchannel <https://t.me/pythontelegrambotchannel>`_.

**Major Changes:**

- Full Support for API 5.6 (`2835`_)

**Minor Changes & Doc fixes:**

- Update Copyright to 2022 (`2836`_)
- Update Documentation of ``BotCommand`` (`2820`_)

.. _`2835`: https://github.com/python-telegram-bot/python-telegram-bot/pull/2835
.. _`2836`: https://github.com/python-telegram-bot/python-telegram-bot/pull/2836
.. _`2820`: https://github.com/python-telegram-bot/python-telegram-bot/pull/2820

Links

• PyPI: https://pypi.org/project/python-telegram-bot
• Changelog: https://pyup.io/changelogs/python-telegram-bot/
• Homepage: https://python-telegram-bot.org/

[pyup-bot]

Closing this in favor of #49