chore(deps): update actions/upload-pages-artifact action to v4 (#109)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/pkgdown.yml

@@ -37,7 +37,7 @@ jobs:
       - name: Build pkgdown site
         run: Rscript -e 'pkgdown::build_site_github_pages(install = TRUE)'
       - name: Deploy pkgdown site
-        uses: actions/upload-pages-artifact@56afc609e74202658d3ffba0e8f6dda462b719fa # v3.0.1
+        uses: actions/upload-pages-artifact@7b1f4a764d45c48632c6b24a0339c27f5614fb0b # v4.0.0
         with:
           path: docs/
       - name: Deploy pkgdown site