[ReleasePR hybridnetwork] Update device discriminator model (#1950)

Create to sync Azure/azure-rest-api-specs#16316
[ReCreate this PR](https://github.com/azure-resource-manager-schemas/compare/main...AzureSDKAutomation:sdkAuto/hybridnetwork?expand=1)

Author: msftbot[bot]

schemas/2020-01-01-preview/Microsoft.HybridNetwork.json

@@ -294,6 +294,33 @@
     }
   },
   "definitions": {
+    "AzureStackEdgeFormat": {
+      "type": "object",
+      "properties": {
+        "azureStackEdge": {
+          "oneOf": [
+            {
+              "$ref": "#/definitions/SubResource"
+            },
+            {
+              "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
+            }
+          ],
+          "description": "Reference to another sub resource."
+        },
+        "deviceType": {
+          "type": "string",
+          "enum": [
+            "AzureStackEdge"
+          ]
+        }
+      },
+      "required": [
+        "azureStackEdge",
+        "deviceType"
+      ],
+      "description": "The reference to the Azure stack edge device."
+    },
     "CustomProfile": {
       "type": "object",
       "properties": {
@@ -342,19 +369,12 @@
     },
     "DevicePropertiesFormat": {
       "type": "object",
-      "properties": {
-        "azureStackEdge": {
-          "oneOf": [
-            {
-              "$ref": "#/definitions/SubResource"
-            },
-            {
-              "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
-            }
-          ],
-          "description": "Reference to another sub resource."
+      "oneOf": [
+        {
+          "$ref": "#/definitions/AzureStackEdgeFormat"
         }
-      },
+      ],
+      "properties": {},
       "description": "Device properties."
     },
     "ImageReference": {

schemas/2021-05-01/Microsoft.HybridNetwork.json

@@ -306,6 +306,33 @@
     }
   },
   "definitions": {
+    "AzureStackEdgeFormat": {
+      "type": "object",
+      "properties": {
+        "azureStackEdge": {
+          "oneOf": [
+            {
+              "$ref": "#/definitions/SubResource"
+            },
+            {
+              "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
+            }
+          ],
+          "description": "Reference to another sub resource."
+        },
+        "deviceType": {
+          "type": "string",
+          "enum": [
+            "AzureStackEdge"
+          ]
+        }
+      },
+      "required": [
+        "azureStackEdge",
+        "deviceType"
+      ],
+      "description": "The reference to the Azure stack edge device."
+    },
     "CustomProfile": {
       "type": "object",
       "properties": {
@@ -354,19 +381,12 @@
     },
     "DevicePropertiesFormat": {
       "type": "object",
-      "properties": {
-        "azureStackEdge": {
-          "oneOf": [
-            {
-              "$ref": "#/definitions/SubResource"
-            },
-            {
-              "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
-            }
-          ],
-          "description": "Reference to another sub resource."
+      "oneOf": [
+        {
+          "$ref": "#/definitions/AzureStackEdgeFormat"
         }
-      },
+      ],
+      "properties": {},
       "description": "Device properties."
     },
     "ImageReference": {