User Story:

As a user, I want to be able to:

• Pass customer managed keys to the installer

so that

• The installer encrypts the storage accounts created

Acceptance Criteria:

Description of criteria:

• User is able to pass the neccesary information for encryption through the install config
• Storage account created for the control plane use is encrypted

(optional) Out of Scope:

Not encrypting the storage account used for bootstrap

Engineering Details:

• Encryption requires key vault id and user assigned identity keys mentioned here
  https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/storage_account#customer_managed_key
• Storage account must be set to `Premium` and kind to `StorageV2` which is default.

This requires/does not require a design proposal.
This requires/does not require a feature gate.