feat(arm): ensure ACR disables anonymous pulling of images (CKV_AZURE_138)

[rutiNalenger]

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Description

This pull request adds a new check to ensure that Azure Container Registry (ACR) disables anonymous pulling of images. Enabling anonymous image pulling allows anyone to pull images from the registry without authentication, which poses a security risk. This check ensures that the anonymousPullEnabled property is not enabled for ACR SKUs Standard and Premium.

New/Edited policies (Delete if not relevant)

Description

Include a description of what makes it a violation and any relevant external links.

Fix

How does someone fix the issue in code and/or in runtime?

Checklist:

• [v] My code follows the style guidelines of this project
• [v] I have performed a self-review of my own code
• [v] I have commented my code, particularly in hard-to-understand areas
• [v] I have made corresponding changes to the documentation
• [v] I have added tests that prove my feature, policy, or fix is effective and works
• [v] New and existing tests pass locally with my changes
• [v] Any dependent changes have been merged and published in downstream modules

[ChanochShayner]

Nice!