✨ Adds a new decision record about the requirements when testing cluster-stacks

Created by: batistein

This PR introduces a new decision record that presents an extensive discussion about the necessary requirements for testing cluster-stacks. The document lays out the motivations, design considerations, required features, and potential approaches for developing a robust and practical solution for testing cluster-stacks. It underscores the benefits and drawbacks of utilizing a local environment for testing and provides a thorough comparison between using Infrastructure as a Service (IaaS) providers and local environments.

The document proposes a shift from Docker-based testing to a virtual machine-based approach due to Docker's limitations in mimicking real-world production environments accurately. It also emphasizes the need for a detailed evaluation of these and possibly other tools to decide the best path forward.

By implementing this decision record, we aim to establish a foundation for evaluating a suitable solution for testing cluster-stacks. The end goal is to develop a testing environment that closely replicates real-world production scenarios, ensures tester accessibility, and provides reliable and robust test results.

Please review the document and provide your feedback, suggestions, or approval for this proposed change.