Ensure only SSL connections are enabled for Azure Redis Cache

Azure Redis Cache accepts non-SSL connections, this may impact the confidentiality & integrity of data in transit.

In Azure Console -

1. Open the Azure Portal and go to Azure Cache for Redis.
2. Select the Redis Cache you wish to edit.
3. Under Settings, select Advanced Settings.
4. Set Allow access only via SSL to Yes.
5. Ensure Non-SSL Port gets set to Disabled when changing the prior setting.
6. Save.

In Terraform -

1. In the azurerm_redis_cache resource, set enable_non_ssl_port to false.

References:
https://learn.microsoft.com/en-us/azure/azure-cache-for-redis/
https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/redis_cache#enable_non_ssl_port