Bump JamesIves/github-pages-deploy-action from 4.6.4 to 4.6.8 (#834)

Bumps [JamesIves/github-pages-deploy-action](https://github.com/jamesives/github-pages-deploy-action) from 4.6.4 to 4.6.8.
- [Release notes](https://github.com/jamesives/github-pages-deploy-action/releases)
- [Commits](JamesIves/github-pages-deploy-action@v4.6.4...v4.6.8)

---
updated-dependencies:
- dependency-name: JamesIves/github-pages-deploy-action
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/documentation_ghpages.yaml

@@ -81,7 +81,7 @@ jobs:
 
  # Deploy to github pages
  - name: Deploy to github pages
- uses: JamesIves/github-pages-deploy-action@v4.6.4
+ uses: JamesIves/github-pages-deploy-action@v4.6.8
  with:
  BRANCH: gh-pages
  FOLDER: docs/build/html