Separate Fabric-specific message types (#1848)

* Update message de->fabric to v3

* Reinstate get authorization token path which doesn't get called every 5 minutes anymore

* Remove obsolete comment

* Add missing types

* Fix format

* Fix build issue

* Revert "Reinstate get authorization token path which doesn't get called every 5 minutes anymore"

This reverts commit a3f3511043.

* Keep 3 old fabric message types enums for compatibility with the portal

* Re-add warning comment about not changing existing message type enums

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Co-authored-by: Laurent Nguyen <languye@microsoft.com>

src/Contracts/FabricMessagesContract.ts

@@ -1,4 +1,4 @@
-import { AuthorizationToken } from "./MessageTypes";
+import { AuthorizationToken } from "Contracts/FabricMessageTypes";
 
 // This is the version of these messages
 export const FABRIC_RPC_VERSION = "2";