ci: fix pnpm setup

[himself65]

Upstream: https://github.com/pnpm/action-setup/issues/135#issuecomment-2206861174

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Name	Status	Preview	Comments	Updated (UTC)
valtio	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jul 8, 2024 11:07pm

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commit: 3370dbc

valtio

``` npm i https://pkg.pr.new/valtio@920 ```

---

templates

- [default](https://pkg.pr.new/template/d683b46e-4210-4d39-aa55-c304131c0010)

[dai-shi]

Same as: https://github.com/pmndrs/jotai/pull/2646