added readme change related to SFI

Author: Dhruvkumar-Microsoft

docs/CustomizingAzdParameters.md

@@ -21,6 +21,7 @@ By default this template will use the environment name as the prefix to prevent
 | `AZURE_ENV_JUMPBOX_ADMIN_PASSWORD`     | string  | `JumpboxAdminP@ssw0rd1234!` | Specifies the administrator password for the Jumpbox Virtual Machine.      |
 | `AZURE_ENV_COSMOS_SECONDARY_LOCATION`  | string  | *(not set by default)*      | Specifies the secondary region for Cosmos DB. Required if `enableRedundancy` is `true`. |
 | `AZURE_EXISTING_AI_PROJECT_RESOURCE_ID`  | string  | *(not set by default)*      | Specifies the existing AI Foundry Project Resource ID if it needs to be reused. |
+| `APP_ENV`  | string  | `prod`     | Set app environment as `dev` for local debugging |
 ---
 
 ## How to Set a Parameter