[FR][DAC] Consideration: DAC related CI/CD (GH actions) for syncing with Kibana

[brokensound77]

related to #3298

As part of the work to support more detections-as-code workflows, the intent here is to add example CI/CD workflows to support or serve as a reference. The scope should be limited to github actions only.

• review keeping rules synced with concurrent changes between kibana and repo (and race conditions)
• multi branching strategies (test branch and prod branch) also vs GH releases
• modifications to prebuilt rules - maybe
• multi-tenant considerations (cross cluster and cross spaces)
• CLI commands to support

[brokensound77]

I think we can create a dac/ folder off the root directory to include non module things such as these or any other non-code files, and even example code snippets