fix: ensure using @nativescript/nx v20

Author: NathanWalker

packages/nativescript/package.json

@@ -29,7 +29,7 @@
     "migrations": "./migrations.json"
   },
   "dependencies": {
-    "@nativescript/nx": "^19.0.0"
+    "@nativescript/nx": "^20.0.0"
   },
   "peerDependencies": {
     "@nstudio/xplat": "*"