Infra: production pipeline (step 1)

[guilhem-fry]

This PR creates the production environment and deployment capabilities in Pulumi.

• DB deletion protection in production
• Environment follows same naming convention as in staging: ${env}-consent-api
• Fixes a bug in the resource name formatting
• Sanitise the branch name for when there are slashes
• Create a "production" stack to deploy the production environment

[guilhem-fry]

This seems to differ somewhat from the PR description.

• [x] DB deletion protection in production
• [ ] ~Follows the same pattern as naming convention as in staging: ${env}-consent-api~ Does this PR include this work?
• [ ] ~Format the resource names to take into account the max length imposed by GCP~ I think this was already implemented, and this PR includes a bugfux for when trimmable=None
• [x] Sanitise the branch name for when there are slashes
• [x] Create a "production" stack to deploy the production environment

One small comment on the code itself.

Cheers, indeed the resource name formatting is a bugfix. Worth mentioning the naming convention as we are moving away from the previous prod environment that had been manually set up