Added branch to when

.drone.yml

@@ -95,6 +95,7 @@ steps:
     when:
       event:
       - tag
+      branch: [ refs/tags/v* ]
   - name: trigger js lib build
     depends_on: [clone]
     image: plugins/downstream
@@ -124,4 +125,5 @@ steps:
       - SOURCE_TAG=$DRONE_TAG
     when:
       event:
-      - tag
+      - tag
+