Add zipped downloadable preview files

.github/workflows/pull_request.yml

@@ -110,6 +110,9 @@ jobs:
           echo site status ${{steps.site.outcome}}
           exit 1
 
+      - name: Website preview for download
+        run: zip website-preview.zip docs/* -r
+
       # Commit the rendered website files
       - name: Commit rendered website files to preview branch
         id: commit
@@ -123,9 +126,6 @@ jobs:
           git push --force || echo "No changes to commit"
         shell: bash
 
-      - name: Website preview for download
-        run: zip website-preview.zip docs/* -r
-
       - name: Upload artifact for deployment job
         uses: actions/upload-artifact@v2
         with:
@@ -145,6 +145,7 @@ jobs:
         run: |
           course_name=$(head -n 1 _website.yml | cut -d'"' -f 2| tr " " "-")
           website_link=$(echo "https://htmlpreview.github.io/?https://raw.githubusercontent.com/$GITHUB_REPOSITORY/preview-${{ github.event.pull_request.number }}/docs/index.html")
+          docs_link=$echo "https://raw.githubusercontent.com/$GITHUB_REPOSITORY/preview-${{ github.event.pull_request.number }}/website-preview.zip"
           echo ::set-output name=website_link::$website_link
           echo ::set-output name=time::$(date +'%Y-%m-%d')
           echo ::set-output name=commit_id::$GITHUB_SHA
@@ -157,7 +158,8 @@ jobs:
           comment-id: ${{ steps.fc.outputs.comment-id }}
           issue-number: ${{ github.event.pull_request.number }}
           body: |
-            Re-rendered previews from the latest commit: See [preview of website here](${{ steps.build-components.outputs.website_link }})
+            Quick preview for the latest commit: See [preview of website here](${{ steps.build-components.outputs.website_link }})
+            Comprehensive [downloadable preview files](${{ steps.build-components.outputs.docs_link}})
 
             _Updated at ${{ steps.build-components.outputs.time }} with changes from ${{ steps.build-components.outputs.commit_id }}_
           edit-mode: replace