chore(deps): update dependency ng-packagr to v21.0.0-rc.0

Author: renovate[bot]

libs/angular-ecmascript-intl/package.json

@@ -36,7 +36,7 @@
     "cpy-cli": "^6.0.0",
     "dayjs": "^1.11.13",
     "jsdom": "^27.0.0",
-    "ng-packagr": "21.0.0-next.4",
+    "ng-packagr": "21.0.0-rc.0",
     "vitest": "^4.0.0"
   },
   "sideEffects": false,