Update preview action

Author: chvmvd

.github/workflows/preview.yml

@@ -22,7 +22,7 @@ jobs:
       - name: Execute Notebooks
         uses: ./.github/actions/execute-notebooks
 
-      - name: Calculate BASE_URL
+      - name: Make BASE_URL
         run: echo ${{ github.ref }} | sed "s/[^0-9]//g" | (v=$(cat); echo -e "BASE_URL=/pr-preview/pr-$v/" ) >> $GITHUB_ENV
 
       - name: Build