Update idna to 2.9

[pyup-bot]

This PR updates idna from 2.8 to 2.9.

Changelog

2.9

++++++++++++++++

- Update to Unicode 12.1.0.
- Prohibit A-labels ending with a hyphen (Thanks, Julien Bernard!)
- Future-proofing: Test on Python 3.7 and 3.8, don't immediately
fail should Python 4 come along.
- Made BSD 3-clause license clearer

Links

• PyPI: https://pypi.org/project/idna
• Changelog: https://pyup.io/changelogs/idna/
• Repo: https://github.com/kjd/idna

[codecov-io]

Codecov Report

Merging #83 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #83   +/-   ##
=======================================
  Coverage   78.13%   78.13%           
=======================================
  Files           5        5           
  Lines         247      247           
=======================================
  Hits          193      193           
  Misses         54       54

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 620ad78...e81b280. Read the comment docs.

[pyup-bot]

Closing this in favor of #123