Renamed ShareFileRequestIntent and made it an extensible enum (#22699)

Author: seanmcc-msft

specification/storage/data-plane/Microsoft.FileStorage/preview/2022-11-02/file.json

@@ -6956,12 +6956,11 @@
       "required": false,
       "type": "string",
       "enum": [
-        "none",
         "backup"
       ],
       "x-ms-enum": {
-        "name": "ShareFileRequestIntent",
-        "modelAsString": false
+        "name": "ShareTokenIntent",
+        "modelAsString": true
       }
     },
     "FileType": {