chore(deps): update actions/setup-node action to v6 (#356)

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

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America/Chicago, Automerge - At any time (no schedule defined).

🚦 **Automerge**: Enabled.

♻ **Rebasing**: Whenever PR becomes conflicted, 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/autofix.yml

@@ -18,7 +18,7 @@ jobs:
         uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6
 
       - name: Setup Node.js
-        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+        uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6
         with:
           node-version: '24'
           cache: 'npm'

.github/workflows/check-dist.yml

@@ -34,7 +34,7 @@ jobs:
         uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6
 
       - name: Setup Node.js
-        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+        uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6
         with:
           node-version: 24
           cache: npm

.github/workflows/ci.yml

@@ -23,7 +23,7 @@ jobs:
 
       - name: Setup Node.js
         id: setup-node
-        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+        uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6
         with:
           node-version: 24
           cache: npm