Update requests to 2.24.0

[pyup-bot]

This PR updates requests from 2.23.0 to 2.24.0.

Changelog

2.24.0

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

**Improvements**

- pyOpenSSL TLS implementation is now only used if Python
either doesn't have an `ssl` module or doesn't support
SNI. Previously pyOpenSSL was unconditionally used if available.
This applies even if pyOpenSSL is installed via the
`requests[security]` extra (5443)

- Redirect resolution should now only occur when
`allow_redirects` is True. (5492)

- No longer perform unnecessary Content-Length calculation for
requests that won't use it. (5496)

Links

• PyPI: https://pypi.org/project/requests
• Changelog: https://pyup.io/changelogs/requests/
• Docs: https://requests.readthedocs.io

[pyup-bot]

Closing this in favor of #296