Module for Azure Firewall

Publish a module to Terraform registry that helps to deploy and configure Azure Firewall.

Related Terraform resources:
- https://www.terraform.io/docs/providers/azurerm/r/firewall.html
- https://www.terraform.io/docs/providers/azurerm/r/firewall_application_rule_collection.html
- https://www.terraform.io/docs/providers/azurerm/r/firewall_network_rule_collection.html

Start by reviewing the three linked azurerm firewall resources and the Terraform Registry publishing requirements. Define the module's deployment and configuration scope from those resources, then verify that the completed module is published to the Terraform Registry and supports the intended Azure Firewall setup.

Written by the indexing model from the issue text.