Support Platform CLI

[doshitan]

Ticket

Resolves navapbc/platform-cli#6

Changes

• Add copier.yml config file
• Move template files into template/
• Move Docker Compose files from project root to {{app_name}}/. And tag the
  app services with {{app_name}}. In a multi-app environment, it is
  unreasonable (and high source of conflicts on update) for a single application
  template to provide a root Compose file. So apps should provide their own
  Compose files, the the project can import them into one project-wide Compose
  file if desired.
• Move .grype.yml from project root to {{app_name}}/. Upstream scanning CI
  has been updated to apply app-specific configs when running for those apps.
• Remove old install/update scripts
• Update from unsupported GitHub actions
• Update template CD to use platform-cli

Testing

navapbc/platform-test-nextjs#95