chore(deps): update actions/setup-node action to v6 (#192)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/setup-node](https://redirect.github.com/actions/setup-node) |
action | major | `v5` -> `v6` |

---

### Release Notes

<details>
<summary>actions/setup-node (actions/setup-node)</summary>

###
[`v6`](https://redirect.github.com/actions/setup-node/compare/v5...v6)

[Compare
Source](https://redirect.github.com/actions/setup-node/compare/v5...v6)

</details>

---

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---

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---

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.github/workflows/pr.yaml

@@ -10,7 +10,7 @@ jobs:
       - name: setup pnpm
         uses: pnpm/action-setup@41ff72655975bd51cab0327fa583b6e92b6d3061 # v4
       - name: setup node
-        uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5
+        uses: actions/setup-node@2028fbc5c25fe9cf00d9f06a71cc4710d4507903 # v6
         with:
           node-version: 21
           cache: "pnpm"
@@ -30,7 +30,7 @@ jobs:
       - name: setup pnpm
         uses: pnpm/action-setup@41ff72655975bd51cab0327fa583b6e92b6d3061 # v4
       - name: setup node
-        uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5
+        uses: actions/setup-node@2028fbc5c25fe9cf00d9f06a71cc4710d4507903 # v6
         with:
           node-version: 22
           cache: "pnpm"