pip (deps): bump the python-dependencies group across 2 directories with 2 updates

Bumps the python-dependencies group with 1 update in the / directory: [pytest-nhsd-apim](https://github.com/NHSDigital/pytest-nhsd-apim).
Bumps the python-dependencies group with 1 update in the /sandbox directory: [gunicorn](https://github.com/benoitc/gunicorn).


Updates `pytest-nhsd-apim` from 3.4.5 to 4.0.0
- [Commits](https://github.com/NHSDigital/pytest-nhsd-apim/commits)

Updates `gunicorn` from 22.0.0 to 23.0.0
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@22.0.0...23.0.0)

---
updated-dependencies:
- dependency-name: pytest-nhsd-apim
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: python-dependencies
- dependency-name: gunicorn
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: python-dependencies
...

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

Author: dependabot[bot]