ci: allow to run docs build on demand

.github/workflows/deploy.yml

@@ -1,10 +1,11 @@
 name: Deploy
 on:
+  workflow_dispatch:
   push:
     branches:
       - main
     paths:
-      - 'docs/**'
+      - "docs/**"
 
 jobs:
   deploy:
@@ -34,7 +35,7 @@ jobs:
         uses: actions/upload-pages-artifact@v3
         with:
           # Upload entire repository
-          path: 'docs/book'
+          path: "docs/book"
       - name: Deploy to GitHub Pages
         id: deployment
         uses: actions/deploy-pages@v4