IP White List integration tests for ISO example template

[ThePhen]

Description

*As an ISO template engineer, I'd like to have integration tests that verify IP White List configuration is enacted on AZ resources.

As of this writing, there are unit tests that very that terraform plans reflect IP white list configuration settings, but they do not actually test that terraform apply has enacted such config upon Key Vaults and ACRs. Integration tests could cover this.

Acceptance Criteria

Reference: [Done-Done Checklist] (https://github.com/Microsoft/code-with-engineering-playbook/blob/master/Engineering/BestPractices/DoneDone.md)

• IP white list configuration (e.g. provided by TF_VAR_resource_ip_whitelist) is enacted on the ACR and key vault resources under control of the ISO template.
• Changing the IP whitelist between successive builds results in corrected configuration of the implicated resources

See PR #350 for more, especially this comment.