[RULE] Zone redundancy check for Cache for Redis

[Leandroesc]

Existing rule

No response

Suggested rule

Currently there's no rule to check for Cache for Redis Availability Zone protection. It would be good to align the rules with all other reliability checks done by PSRule already for Availability Zone protection.

Pillar

None

Additional context

This will help improve checking for deployed resources using the steps in this link: https://azure.github.io/PSRule.Rules.Azure/export-rule-data/
https://learn.microsoft.com/en-us/azure/azure-cache-for-redis/cache-how-to-zone-redundancy

[BernieWhite]

Existing rule exists https://azure.github.io/PSRule.Rules.Azure/en/rules/Azure.Redis.AvailabilityZone/

However, it only provides the recommendation if the tier is premium. We should remove that requirement as we have been doing with other rules as it is confusing for customers.

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Work required:

• Update the rule to flag is the resource is not a premium SKU or if zones is not configured.