[ReleasePR purview] Adding UAMI properties to the swagger (#2152)

Create to sync Azure/azure-rest-api-specs#16947
[ReCreate this PR](https://github.com/azure-resource-manager-schemas/compare/main...AzureSDKAutomation:sdkAuto/purview?expand=1)

Author: msftbot[bot]

schemas/2021-07-01/Microsoft.Purview.json

@@ -135,7 +135,8 @@
             {
               "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
             }
-          ]
+          ],
+          "description": "External Cloud Service connectors"
         },
         "managedResourceGroupName": {
           "type": "string",
@@ -201,7 +202,8 @@
     },
     "CloudConnectors": {
       "type": "object",
-      "properties": {}
+      "properties": {},
+      "description": "External Cloud Service connectors"
     },
     "Identity": {
       "type": "object",
@@ -211,14 +213,31 @@
             {
               "type": "string",
               "enum": [
-                "SystemAssigned"
+                "None",
+                "SystemAssigned",
+                "UserAssigned"
               ]
             },
             {
               "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
             }
           ],
           "description": "Identity Type."
+        },
+        "userAssignedIdentities": {
+          "oneOf": [
+            {
+              "type": "object",
+              "additionalProperties": {
+                "$ref": "#/definitions/UserAssignedIdentity"
+              },
+              "properties": {}
+            },
+            {
+              "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
+            }
+          ],
+          "description": "User Assigned Identities"
         }
       },
       "description": "The Managed Identity of the resource"
@@ -292,6 +311,11 @@
         }
       },
       "description": "The private link service connection state."
+    },
+    "UserAssignedIdentity": {
+      "type": "object",
+      "properties": {},
+      "description": "Uses client ID and Principal ID"
     }
   }
 }