ci: run next.js repo e2e tests on node 18.18.0 (#2542)

The minimum supported version for canary got bumped recently.

We could use different versions per next.js version but it probably isn't worth it here.

Author: serhalp

Diff for: .github/workflows/test-e2e.yml

@@ -19,7 +19,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  NODE_VERSION: 18.17.1
+  NODE_VERSION: 18.18.0
   PNPM_VERSION: 8.9.0
   NEXT_REPO: vercel/next.js
   NEXT_TEST_MODE: deploy