Backend: Support `@~latest` version when including components

Problem statement

As a user I would like to include always the latest version of a given component. For latest we intend the most recent (official) release that is available on the CI catalog.

Proposal

include:
  - component: gitlab.com/gitlab-org/dast@~latest

References

https://gitlab.com/gitlab-org/gitlab/-/blob/master/doc/architecture/blueprints/ci_pipeline_components/index.md#the-component-version

Implementation

backend	MR
Support @~latest version when including components	!115756 (merged)