test(v10/nextjs): Pin nextjs-16-cf-workers latest variant to Next.js 16.3 (#25130)

Backport of: #25118

Co-authored-by: Charly Gomez <charly.gomez1310@gmail.com>

Author: msonnb

dev-packages/e2e-tests/test-applications/nextjs-16-cf-workers/package.json

@@ -13,7 +13,7 @@
     "test:prod": "TEST_ENV=production playwright test",
     "test:build": "pnpm install && pnpm cf:build",
     "test:build-canary": "pnpm install && pnpm add next@canary && pnpm cf:build",
-    "test:build-latest": "pnpm install && pnpm add next@latest && pnpm cf:build",
+    "test:build-latest": "pnpm install && pnpm add next@16.3 && pnpm cf:build",
     "test:assert": "pnpm test:prod"
   },
   "dependencies": {