Update pytest-runner to 2.12.2

[pyup-bot]

There's a new version of pytest-runner available.
You are currently using 2.11.1. I have updated it to 2.12.2

These links might come in handy: PyPI | Changelog | Repo

Changelog

2.12.2

• 33: Packaging refresh.

2.12.1

• 32: Fix support for dependency_links.

2.12

• 30: Rework support for --allow-hosts and
  --index-url, removing dependence on
  setuptools.Distribution's private member.
  Additionally corrects logic in marker evaluation
  along with unit tests!

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖

[pyup-bot]

Closing this in favor of #22

[coveralls]

Coverage remained the same at 61.252% when pulling 6336f82 on pyup-update-pytest-runner-2.11.1-to-2.12.2 into 9a925d5 on master.