add build_html.sh change trigger to deploy_main workflow

Author: trevorcampbell

.github/workflows/deploy_main_preview.yml

@@ -4,7 +4,8 @@ on:
     branches:
       - main
     paths:
-      - source/**
+      - 'source/**'
+      - 'build_html.sh'
 
 jobs:
   deploy-main-preview: