Remove static ms.date from global metadata

Author: garycentric

sharepoint/docfx.json

@@ -47,7 +47,6 @@
       "manager": "meerak",
       "ms.author": "pamgreen",
       "ms.devlang": "powershell",
-      "ms.date": "09/08/2021",
       "ms.topic": "reference",
       "contributors_to_exclude": [
         "rjagiewich",