Enable two test cases, and drop the workaround for x-ms-enum (#677)

Author: dolauli

tests-upgrade/Configuration.json

@@ -23,13 +23,15 @@
     "datamodels-datatypes-array",
     "datamodels-datatypes-integer",
     "datamodels-datatypes-string",
+    "datamodels-datatypes-object",
     "datamodels-combineschema",
     "directive-model",
     "directive-tableformat",
     "extension-ms-azureresource",
     "extension-ms-clientflatten",
     "extension-ms-clientname",
     "extension-ms-discriminatorvalue",
+    "extension-ms-enum",
     "extension-ms-examples",
     "extension-ms-longruningoperation",
     "extension-ms-mutability",

tests-upgrade/readme.azure.noprofile.md

@@ -44,7 +44,4 @@ directive:
     set:
       default:
         script: '(Get-AzContext).Subscription.Id'
-  - from: swagger-document
-    where: $
-    transform: return $.replace(/"modelAsString":\ true/g, '"modelAsString":\ false')
 ```