Bump virtualenv from 20.39.0 to 21.1.0

Bumps [virtualenv](https://github.com/pypa/virtualenv) from 20.39.0 to 21.1.0.
- [Release notes](https://github.com/pypa/virtualenv/releases)
- [Changelog](https://github.com/pypa/virtualenv/blob/main/docs/changelog.rst)
- [Commits](pypa/virtualenv@20.39.0...21.1.0)

---
updated-dependencies:
- dependency-name: virtualenv
  dependency-version: 21.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

requirements.txt

@@ -1,5 +1,5 @@
 packaging == 26.0 --hash=sha256:00243ae351a257117b6a241061796684b084ed1c516a08c48a3f7e147a9d80b4
-virtualenv == 20.39.0 --hash=sha256:44888bba3775990a152ea1f73f8e5f566d49f11bbd1de61d426fd7732770043e --hash=sha256:a15f0cebd00d50074fd336a169d53422436a12dfe15149efec7072cfe817df8b
+virtualenv == 21.2.0 --hash=sha256:1720dc3a62ef5b443092e3f499228599045d7fea4c79199770499df8becf9098 --hash=sha256:1bd755b504931164a5a496d217c014d098426cddc79363ad66ac78125f9d908f
 virtualenv-clone == 0.5.7 --hash=sha256:44d5263bceed0bac3e1424d64f798095233b64def1c5689afa43dc3223caf5b0
 certifi == 2026.2.25 --hash=sha256:027692e4402ad994f1c42e52a4997a9763c646b73e4096e4d5d6db8af1d6f0fa --hash=sha256:e887ab5cee78ea814d3472169153c2d12cd43b14bd03329a39a9c6e2e80bfba7
 setuptools == 82.0.0 --hash=sha256:22e0a2d69474c6ae4feb01951cb69d515ed23728cf96d05513d36e42b62b37cb --hash=sha256:70b18734b607bd1da571d097d236cfcfacaf01de45717d59e6e04b96877532e0