Revert "Clean gh-pages branch on builds"

This reverts commit 6f6f38a.

Author: VisruthSK

.github/workflows/pkgdown.yaml

@@ -47,6 +47,6 @@ jobs:
       - name: Deploy to GitHub pages 🚀
         uses: JamesIves/github-pages-deploy-action@v4
         with:
-          clean: true
+          clean: false
           branch: gh-pages
           folder: docs