update drone config

.drone.yml

@@ -13,8 +13,6 @@ steps:
   when:
     branch:
       - main
-    event:
-      - push
 - name: docker-build
   image: plugins/docker
   settings:
@@ -26,8 +24,10 @@ steps:
     tags: latest
     dry_run: true
   when:
-    exclude:
+    branch:
-      branch:
+      exclude:
         - main
-      event:
+when:
-        - push
+  event:
+    include:
+      - push