Replace deprecated skip_provider_registration property

[dawidstrozak]

Jira link

N/A

Change description

Replace skip_provider_registration deprecated property which was used to skip full 68 provider registration by Terraform.
Newer Terraform versions replaced this with resource_provider_registrations which has 5 different registration modes as recommended by Microsoft.
Statement resource_provider_registrations="none" is equivalent to previous skip_provider_registration="true" - it means no resource providers are registered.

For more details read: https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/guides/4.0-upgrade-guide?product_intent=terraform#improved-resource-provider-registration

Testing done

I tested this change by implementing it in my lab Terraform which is based on this repo and running the pipeline successfully:
https://dev.azure.com/hmcts/PlatformOperations/_build/results?buildId=711337&view=results

Checklist

• commit messages are meaningful and follow good commit message guidelines
• (N/A) README and other documentation has been updated / added (if needed)
• (N/A) tests have been updated / new tests has been added (if needed)
• (NO) Does this PR introduce a breaking change