Bump pipenv in /python/helpers in the pipenv group across 1 directory

Bumps the pipenv group with 1 update in the /python/helpers directory: [pipenv](https://github.com/pypa/pipenv).


Updates `pipenv` from 2024.4.1 to 2026.6.1
- [Release notes](https://github.com/pypa/pipenv/releases)
- [Changelog](https://github.com/pypa/pipenv/blob/main/CHANGELOG.md)
- [Commits](pypa/pipenv@v2024.4.1...v2026.6.1)

---
updated-dependencies:
- dependency-name: pipenv
  dependency-version: 2026.0.3
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: pipenv
...

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

Author: dependabot[bot]

python/helpers/requirements.txt

@@ -2,7 +2,7 @@ pip==24.2
 pip-tools==7.5.3
 flake8==7.3.0
 hashin==1.0.5
-pipenv==2024.4.1
+pipenv==2026.6.1
 plette==2.1.0
 poetry==2.2.1
 pytest==8.3.5