deps: bump virtualenv from 20.26.2 to 20.26.6

Bumps [virtualenv](https://github.com/pypa/virtualenv) from 20.26.2 to 20.26.6.
- [Release notes](https://github.com/pypa/virtualenv/releases)
- [Changelog](https://github.com/pypa/virtualenv/blob/main/docs/changelog.rst)
- [Commits](pypa/virtualenv@20.26.2...20.26.6)

---
updated-dependencies:
- dependency-name: virtualenv
  dependency-type: indirect
...

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

requirements-dev.txt

@@ -107,7 +107,7 @@ typing-extensions==4.12.1
     # via
     #   -c requirements.txt
     #   black
-virtualenv==20.26.2
+virtualenv==20.26.6
     # via pre-commit
 wheel==0.43.0
     # via pip-tools