add tag pipeline

.drone.yml

@@ -12,3 +12,25 @@ steps:
         from_secret: dockerhub_username
       password:
         from_secret: dockerhub_password
+
+---
+kind: pipeline
+name: tags
+
+steps:
+  - name: docker
+    image: plugins/docker
+    settings:
+      repo: eumau/debian
+      username:
+        from_secret: dockerhub_username
+      password:
+        from_secret: dockerhub_password
+      tags:
+        - ${DRONE_TAG}
+      build_args:
+        - DEBIAN_VERSION=${DRONE_TAG}
+
+trigger:
+  event:
+    - tag