Don't clean when deploying preview

Author: m-aciek

.github/workflows/update.yml

@@ -34,7 +34,7 @@ jobs:
         with:
           folder: build
           target-folder: ${{ github.ref_name }}
-          clean: true
+          clean: false
           git-config-name: github-actions[bot]
           git-config-email: 41898282+github-actions[bot]@users.noreply.github.com
       - name: Debug index.html if pull request