Update pre-commit to 2.12.1

[pyup-bot]

This PR updates pre-commit from 2.11.1 to 2.12.1.

Changelog

2.12.1

===================

Fixes
- Fix race condition when stashing files in multiple parallel invocations
 - 1881 PR by adamchainz.
 - 1880 issue by adamchainz.

2.12.0

===================

Features
- Upgrade rbenv.
 - 1854 PR by asottile.
 - 1848 issue by sirosen.

Fixes
- Give command length a little more room when running batch files on windows
so underlying commands can expand further.
 - 1864 PR by asottile.
 - pre-commit/mirrors-prettier7 issue by DeltaXWizard.
- Fix permissions of root folder in ruby archives.
 - 1868 PR by asottile.

Links

• PyPI: https://pypi.org/project/pre-commit
• Changelog: https://pyup.io/changelogs/pre-commit/
• Repo: https://github.com/pre-commit/pre-commit

[coveralls]

Coverage remained the same at 86.667% when pulling 835ca4b on pyup-update-pre-commit-2.11.1-to-2.12.1 into e3b6dee on master.

[pyup-bot]

Closing this in favor of #301