[ReleasePR storagecache] [Hub Generated] Review request for Microsoft.StorageCache to add version stable/2021-03-01 (#1789)

Create to sync Azure/azure-rest-api-specs#15013
[ReCreate this PR](https://github.com/azure-resource-manager-schemas/compare/master...AzureSDKAutomation:sdkAuto/storagecache?expand=1)

Author: msftbot[bot]

schemas/2021-03-01/Microsoft.StorageCache.json

@@ -337,6 +337,7 @@
         },
         "ntpServer": {
           "type": "string",
+          "default": "time.windows.com",
           "description": "NTP server IP Address or FQDN for the cache to use. The default is time.windows.com."
         }
       },
@@ -685,6 +686,7 @@
         },
         "nfsAccessPolicy": {
           "type": "string",
+          "default": "default",
           "description": "Name of the access policy applied to this junction."
         },
         "nfsExport": {