oops that was supposed to be filled in, it wasnt a keyword

.github/workflows/build_site.yaml

@@ -3,7 +3,8 @@ name: Deploy Jekyll site to Pages
 on:
   # Runs on pushes targeting the default branch
   push:
-    branches: [$default-branch]
+    branches: 
+      - master
 
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch: