Drone: only build & push container on tag/promote

.drone.yml

@@ -13,10 +13,10 @@ services:
     privileged: true
     environment:
       DOCKER_TLS_CERTDIR: ""
-#    when:
+    when:
-#      event:
+      event:
-#        - tag
+        - tag
-#        - promote
+        - promote
 
 steps:
   - name: node.js build
@@ -43,16 +43,16 @@ steps:
       DOCKER_HOST: tcp://localhost:2375
       DOCKER_REGISTRY:
         from_secret: DOCKER_REGISTRY
-#    when:
+    when:
-#      event:
+      event:
-#        - tag
+        - tag
-#        - promote
+        - promote
 
   - name: k8s rollout
     image: bitnami/kubectl:latest
     commands:
       - kubectl rollout restart -n noded deployment/noded-frontend
-#    when:
+    when:
-#      event:
+      event:
-#        - tag
+        - tag
-#        - promote
+        - promote