feat(arm): ARM AppServiceSlotMinTLS - CKV_AZURE_154

[RachelBorzi]

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Description

Added new policy for - AppServiceSlotMinTLS - CKV_AZURE_154

Fixes # (issue)

New/Edited policies (Delete if not relevant)

Description

policy to ensure the App service slot is using the latest version of TLS encryption

Fix

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

Checklist:

• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] I have added tests that prove my feature, policy, or fix is effective and works
• [x] New and existing tests pass locally with my changes