Update deploy.yml

Author: liganega

.github/workflows/deploy.yml

@@ -5,7 +5,7 @@ name: Jupyter Book (via myst) GitHub Pages Deploy
 on:
   push:
     # Runs on pushes targeting the default branch
-    branches: [main]
+    branches: [master]
 env:
   # `BASE_URL` determines, relative to the root of the domain, the URL that your site is served from.
   # E.g., if your site lives at `https://mydomain.org/myproject`, set `BASE_URL=/myproject`.