Bump peaceiris/actions-gh-pages from 3.6.4 to 3.8.0

Bumps [peaceiris/actions-gh-pages](https://github.com/peaceiris/actions-gh-pages) from 3.6.4 to 3.8.0.
- [Release notes](https://github.com/peaceiris/actions-gh-pages/releases)
- [Changelog](https://github.com/peaceiris/actions-gh-pages/blob/main/CHANGELOG.md)
- [Commits](peaceiris/actions-gh-pages@v3.6.4...v3.8.0)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/build.yml

@@ -69,7 +69,7 @@ jobs:
       run: mkdocs build
 
     - name: Deploy
-      uses: peaceiris/actions-gh-pages@v3.6.4
+      uses: peaceiris/actions-gh-pages@v3.8.0
       env:
         ACTIONS_DEPLOY_KEY: ${{ secrets.ACTIONS_DEPLOY_KEY }}
         PUBLISH_BRANCH: gh-pages

.github/workflows/test.yml

@@ -59,7 +59,7 @@ jobs:
         run: mkdocs build
 
       - name: Deploy
-        uses: peaceiris/actions-gh-pages@v3.6.4
+        uses: peaceiris/actions-gh-pages@v3.8.0
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./site