chore(deps): update actions/setup-node action to v6 (#458)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/setup-node](https://redirect.github.com/actions/setup-node) |
action | major | `v4` → `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)

###
[`v5`](https://redirect.github.com/actions/setup-node/compare/v4...v5)

[Compare
Source](https://redirect.github.com/actions/setup-node/compare/v4...v5)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "before 5am on monday" in timezone
Europe/London, Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR is behind base branch, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

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.github/workflows/release.yml

@@ -18,7 +18,7 @@ jobs:
           fetch-depth: 0
           persist-credentials: false
 
-      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+      - uses: actions/setup-node@6044e13b5dc448c55e2357c09f80417699197238 # v6
         with:
           node-version: 'latest'
       - uses: oven-sh/setup-bun@735343b667d3e6f658f44d0eca948eb6282f2b76 # v2