chore(deps): update actions/configure-pages action to v5 (#86)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[actions/configure-pages](https://redirect.github.com/actions/configure-pages)
| action | major | `v4` -> `v5` |

---

### Release Notes

<details>
<summary>actions/configure-pages (actions/configure-pages)</summary>

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

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

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

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

♻ **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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View the [repository job
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.github/workflows/mdbook.yml

@@ -32,7 +32,7 @@ jobs:
 
       - name: Setup Pages
         id: pages
-        uses: actions/configure-pages@1f0c5cde4bc74cd7e1254d0cb4de8d49e9068c7d # v4
+        uses: actions/configure-pages@983d7736d9b0ae728b81ab479565c72886d7745b # v5
 
       - name: Build course
         run: |