[OPTIMIZATION] Cleanup core demo use cases

[eemrdog]

Cleanup core demo use cases that will be maintained by Ace-Box

[IgnacioGoldman]

The current demo/use_cases are:

• demo-ar-workflows-ansible
• demo-ar-workflows-gitlab
• demo-auto-remediation-ansible
• demo-monaco-gitops
• demo-quality-gates-gitlab
• demo-quality-gates-jenkins
• demo-release-validation-srg-gitlab
• demo-security-gates-jenkins

Some of them need to be deprecated:

• demo-quality-gates-gitlab
• demo-quality-gates-jenkins

The rest will be compacted into 1, that will extend the First Steps into Dynatrace Observability.

Idea

Create a branch for https://github.com/dynatrace-ace/basic-dt-demo, called e2e-ACEBox-test. The branch will be used as an E2E test for the ACE-Box, and replace the demo_all feature. It also can be used as a more complex demo scenario, covering the following use cases:

• ar-workflows: release autoremediation using Dynatrace
• monaco: Dynatrace monitoring as code capabilities
• release-validation-srg: automated release validation by Dynatrace
• security-gates: automated security release validation by Dynatrace