MS Learn document update to provide guidance on integrating security evaluations in DevOps pipeline

Updates to the MS Learn documentation to position AI-assisted security evaluations using the AI Evaluations SDK as part of the DevSecOps process. Most customers we've discussed with prefer running security evaluations "on submit of PR" as a security check to ensure the guardrails are effective. The current documentation lacks this clarity.

We learned when implementing secuerity evals for customer that there is a lack of clear integration capabilities (or at least the guidance around it) for the Azure AI Security Evaluations SDK within DevOps pipelines. Customers feel this absence hinders their ability to detect vulnerabilities early and efficiently, resulting in the accumulation of security debt over time

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