Set Azure Pipeline task status to warning when warning(s) exist from Pulumi Policy-as-Code

[house-of-mistry]

Currently, when policy violation warnings exist on a stack, the status for the Azure pipeline task is green. Teams need to parse the logs to determine whether any warnings exist. This can be problematic if a new policy is rolled out, and teams forget to review the logs if no infrastructure changes were made. By leveraging the Azure task status options, teams can easily identify when such warnings exist.

Alternatively, we would need to create a powershell task, leverage the Pulumi REST api to pull the stack details, determine if any warnings exist, and set the appropriate task status where appropriate.