docs: only run workflow when docs are updated

.github/workflows/astro.yml

@@ -1,14 +1,12 @@
 name: Deploy to GitHub Pages
 
 on:
-  # Trigger the workflow every time you push to the `main` branch
-  # Using a different branch name? Replace `main` with your branch’s name
   push:
     branches: [main]
-  # Allows you to run this workflow manually from the Actions tab on GitHub.
-  workflow_dispatch:
+    paths:
+      - 'docs/**'
+      - '.github/workflows/**'
 
-# Allow this job to clone the repo and create a page deployment
 permissions:
   contents: read
   pages: write