Add missing workflow

Author: billnapier

.github/workflows/publish_docs.yml

@@ -2,6 +2,8 @@ name: 'Publish Docs Site'
 
 on:
   push:
+    branches:
+      - main
   workflow_dispatch:
 
 permissions:
@@ -19,17 +21,10 @@ jobs:
         src: 'docs'
         dst: 'generated-pages'
     - name: 'Upload artifact'
-      if: github.ref == 'refs/heads/main'
       uses: 'actions/upload-pages-artifact@v3'
       with:
         path: 'generated-pages'
-    - name: 'Deploy GitHub Pages Preview'
-      if: github.ref != 'refs/heads/main'
-      uses: rossjrw/pr-preview-action@v1
-      with:
-        source-dir: './generated-pages/'
   deploy:
-    if: github.ref == 'refs/heads/main'
     environment:
       name: 'github-pages'
       url: '${{ steps.deployment.outputs.page_url }}'