[test] Ignore pnpm update notifier (#84328)
This notification even pops up in our e2e test:
```
╭───────────────────────────────────────────────────────────────╮
│ |
│ Update available! 8.15.7 → 10.17.1. │
│ |
| Changelog: │
│ https://github.com/pnpm/pnpm/releases/tag/v10.17.1 │
│ Run "corepack prepare pnpm@10.17.1 --activate" to update. │
│ │
│ Follow @pnpmjs for updates: https://twitter.com/pnpmjs │
│ │
╰───────────────────────────────────────────────────────────────╯
```
I'd consider this message noise. If we want to be notified of updates, we can subscribe to pnpm release. Constantly notifying is annoying.
