refactor: persist request handles under tab saveContext

Only the IDs (workspace, provider & request IDs) to restore the handle are stored under `localStorage` and the handle is restored back at runtime.

packages/hoppscotch-common/src/components/collections/SaveRequest.vue

@@ -277,6 +277,7 @@ const saveRequestAs = async () => {
         workspaceID,
         providerID,
         requestID,
+        requestHandle,
       },
     }