Bump virtualenv from 20.27.1 to 20.28.0 in the pip-dependencies group (#393)

Bumps the pip-dependencies group with 1 update: [virtualenv](https://github.com/pypa/virtualenv).


Updates `virtualenv` from 20.27.1 to 20.28.0
- [Release notes](https://github.com/pypa/virtualenv/releases)
- [Changelog](https://github.com/pypa/virtualenv/blob/main/docs/changelog.rst)
- [Commits](pypa/virtualenv@20.27.1...20.28.0)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -12,7 +12,7 @@ pytest==6.2.4
 pytest-runner==5.3.1
 toml==0.10.2
 tox==3.23.1
-virtualenv==20.27.1
+virtualenv==20.28.0
 setuptools==72.0.0
 docopt==0.6.2
 tabulate==0.9.0