feat: add auto-triage via Backstage

[simaarfania]

Related to Hackathon project which is built off of https://github.com/grafana/deployment_tools/issues/239391.

• Triggers: When issues are opened with "Affected Resource(s)"
• Queries: Backstage API to find resource ownership -- needs to be tested*
• Assigns: Issues to team GitHub projects automatically needs to be tested
• Labels: Adds team/[name] labels
• Notifies: Mentions owning teams in comments

[github-actions]

In order to lower resource usage and have a faster runtime, PRs will not run Cloud tests automatically.
To do so, a Grafana Labs employee must trigger the cloud acceptance tests workflow manually.