removed duplicate object defination

Author: gargankit-microsoft

specification/workloads/resource-manager/Microsoft.Workloads/preview/2021-12-01-preview/phpWorkloads.json

@@ -571,18 +571,6 @@
         }
       ]
     },
-    "ManagedServiceIdentityType": {
-      "description": "Type of managed service identity (only None, UserAssigned types are allowed).",
-      "enum": [
-        "None",
-        "UserAssigned"
-      ],
-      "type": "string",
-      "x-ms-enum": {
-        "name": "ManagedServiceIdentityType",
-        "modelAsString": true
-      }
-    },
     "phpWorkloadResourceProperties": {
       "description": "PHP workload resource properties",
       "type": "object",