Bump the all-dependencies group with 2 updates

Updates the requirements on [virtualenv](https://github.com/pypa/virtualenv) and [tox](https://github.com/tox-dev/tox) to permit the latest version.

Updates `virtualenv` to 20.35.3
- [Release notes](https://github.com/pypa/virtualenv/releases)
- [Changelog](https://github.com/pypa/virtualenv/blob/main/docs/changelog.rst)
- [Commits](pypa/virtualenv@20.34.0...20.35.3)

Updates `tox` to 4.31.0
- [Release notes](https://github.com/tox-dev/tox/releases)
- [Changelog](https://github.com/tox-dev/tox/blob/main/docs/changelog.rst)
- [Commits](tox-dev/tox@4.30.0...4.31.0)

---
updated-dependencies:
- dependency-name: virtualenv
  dependency-version: 20.35.3
  dependency-type: direct:production
  dependency-group: all-dependencies
- dependency-name: tox
  dependency-version: 4.31.0
  dependency-type: direct:production
  dependency-group: all-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements-build.txt

@@ -1,6 +1,6 @@
 # This file is used for running tox, flake8 and building the wheel
 pip~=25.2
-virtualenv~=20.34
+virtualenv~=20.35
 setuptools~=80.9
 logilab-common~=2.1
-tox~=4.30
+tox~=4.31