Renovate: peaceiris/actions-gh-pages to v4 (#243)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[peaceiris/actions-gh-pages](https://togithub.com/peaceiris/actions-gh-pages)
| action | major | `v3` -> `v4` |

---

### Release Notes

<details>
<summary>peaceiris/actions-gh-pages
(peaceiris/actions-gh-pages)</summary>

###
[`v4`](https://togithub.com/peaceiris/actions-gh-pages/compare/v3...v4)

[Compare
Source](https://togithub.com/peaceiris/actions-gh-pages/compare/v3...v4)

</details>

---

### Configuration

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month" (UTC), Automerge - "every weekday" (UTC).

🚦 **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.

---

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this box

---

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actions/github-pages/jekyll/action.yml

@@ -41,7 +41,7 @@ runs:
     - name: Deploy
       if: github.ref == 'refs/heads/main'
       # yamllint disable-line rule:line-length
-      uses: peaceiris/actions-gh-pages@373f7f263a76c20808c831209c920827a82a2847 # v3
+      uses: peaceiris/actions-gh-pages@4f9cc6602d3f66b9c108549d475ec49e8ef4d45e # v4
       with:
         github_token: ${{ inputs.github-token }}
         publish_dir: >-

actions/python/pdoc/action.yml

@@ -57,7 +57,7 @@ runs:
     - name: Deploy
       if: github.ref == 'refs/heads/main'
       # yamllint disable-line rule:line-length
-      uses: peaceiris/actions-gh-pages@373f7f263a76c20808c831209c920827a82a2847 # v3
+      uses: peaceiris/actions-gh-pages@4f9cc6602d3f66b9c108549d475ec49e8ef4d45e # v4
       with:
         github_token: ${{ inputs.github-token }}
         publish_dir: ${{ inputs.gh-pages-publish-directory }}