Standardise Ansible versions used in repo (v9)

(Originally raised as https://gitlab.developers.cam.ac.uk/uis/devops/devhub/ci-runner-ng/-/issues/24)

I've noticed some discrepancies in the Ansible versions used across this repository:

1. run-ansible-playbook.sh currently uses our ansible-playbook:7 Docker image (Ansible v7).
2. The ansible-check job in .gitlab-ci.yml uses our ansible-playbook:10 image (Ansible v10).
3. The ansible-lint job in .gitlab-ci.yml uses the third-party registry.gitlab.com/pipeline-components/ansible-lint:0.79.0 image, which includes Ansible v11.3.0.

Ideally, all Ansible executions (local and CI) should run the same Ansible version. To achieve this, we may need to bring the linting image in-house, or extend our existing ansible-playbook image to support linting.

But since https://gitlab.developers.cam.ac.uk/uis/devops/devhub/ci-runner-ng created from this template, it makes sense to fix it here and then update copier there.