Bump virtualenv from 20.29.3 to 20.31.2

Bumps [virtualenv](https://github.com/pypa/virtualenv) from 20.29.3 to 20.31.2.
- [Release notes](https://github.com/pypa/virtualenv/releases)
- [Changelog](https://github.com/pypa/virtualenv/blob/main/docs/changelog.rst)
- [Commits](pypa/virtualenv@20.29.3...20.31.2)

---
updated-dependencies:
- dependency-name: virtualenv
  dependency-version: 20.31.2
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements.txt

@@ -46,4 +46,4 @@ sphinxcontrib-serializinghtml==2.0.0
 sphinxcontrib-spelling==8.0.1
 typing_extensions==4.12.2
 urllib3==2.3.0
-virtualenv==20.29.3
+virtualenv==20.31.2