CMS Preview EKS servers should update after Next Build production tag/deploy

[timcosgrove]

Requirements

After a new version of Next Build is deployed for production build & use, the CMS Preview servers should be updated with the latest code and restarted, so that CMS Preview always matches latest code.

### Acceptance criteria
- [ ] https://github.com/department-of-veterans-affairs/va.gov-cms/issues/16857
- [ ] After production deploy, a workflow checks out the latest code to the CMS Preview EKS servers and restarts it
- [ ] If the downtime is longer than around 30 seconds, downtime is handled gracefully ("shield" or hold message)

Background & implementation details

Current implementation:

• GHA workflow is triggered by content-build 'Daily Production Release': https://github.com/department-of-veterans-affairs/content-build/blob/main/.github/workflows/deploy-content-preview-server.yml
• Jenkins jobs are triggered by above workflow. Breadcrumb trail starts here: https://github.com/department-of-veterans-affairs/devops/blob/master/ansible/deployment/config/jenkins-vetsgov/seed_job.groovy#L2385

It is not recommended that Jenkins be used for any of this ticket's work.

### Implementation tasks
- [ ] Use this if it helps you or feel free to delete.

[timcosgrove]

This is superseded by #16863 and #17223