Ensure HTTPS is enabled for Azure Linux Function App

Azure Linux Function App allows HTTP access, this may lead to MiTM and a host of other attacks.

In Azure Console -

1. Open the Azure Portal and go to Function App.
2. Choose the Function App you wish to edit.
3. Under Settings, select Configuration, then the General Settings tab.
4. Set HTTPS Only to on.

In Terraform -

1. In the azurerm_linux_function_app resource, set https_only to true.

References:
https://learn.microsoft.com/en-us/azure/azure-functions/
https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/linux_function_app#https_only