include CI deployment pipeline configuration block in Renovate Bot MRs

This MR brings an evolution to generate_deployment_jobs.py and renovate configuration so that:

• (1) Renovate Bot MRs will have in their description the bloc that governs the generation of deployment pipelines
• (2) the generate_deployment_jobs.py will use it for all renovate MRs, if any check box is checked (and will fallback on the built-in default pipelines for renovate if no checkbox is checkedà

To do (2), some preliminary refactoring was done.

💡 This MR is hence split in multiple commits, and easier to review one commit at a time.

To achieve (1) in a user-friendly and maintainable I'm adding a small tool that will be used to refresh prFooter in renovate.json based on .gitlab/merge_request_templates/Default.md and a CI job that checks that renovate.json was freshly updated with it.