New Terraform Recipe Schema format for supporting private modules

[jasonviviano]

What content needs to be created or modified?

Updating env schema in docs and Terraform Recipe section

Describe the solution you'd like

New schema:

+   recipeConfig: {
+     terraform: {
+       authentication:{
+         git:{  
+           pat:{
+             "github.com":{
+               secret: secretStoreGithub.id
+             },
+             "dev.azure.com": {
+               secret: secretStoreAzureDevOps.id
+             },
+           }
+         }          
+       }
+     }
+   }

Where should the new material be placed?

The associated pull request from the Radius code repo, if applicable

Additional context

AB#11232

[jasonviviano]

Closing as complete