feat: add integration test for policy variable authorization

[cyyan88]

Issue #, if available:

Description of changes:

• Added configuration for CDA that uses policy variables
• Added integration tests for client device authorization flow with policy variables

Why is this change necessary: Ensure that policy variables are compatible with current CDA features

How was this change tested:

• 3 integration tests

Any additional information or context required to review the change:

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[jcosentino11]

Let's update the PR title to use conventional commit format