only deploy when PR's are merged

see https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#running-your-workflow-when-a-pull-request-merges

.github/workflows/ci.yaml

@@ -55,7 +55,7 @@ jobs:
           config: baseUrl=http://localhost:4173/${{ github.event.repository.name }}
 
   deploy:
-    needs: [lint,test]
+    if: github.event.pull_request.merged == true
     environment:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}