chore: revert demo tns-ios version

Author: VladimirAmiorkov

e2e/nested-router-tab-view/package.json

@@ -6,7 +6,7 @@
   "nativescript": {
     "id": "org.nativescript.nestedroutertabview",
     "tns-ios": {
-      "version": "6.0.0-2019-05-16-165318-01"
+      "version": "next"
     },
     "tns-android": {
       "version": "next"