Run downstream builds

See https://git.autonomic.zone/coop-cloud/abra/issues/171.

.drone.yml

@@ -33,7 +33,22 @@ steps:
       - run flake8
       - run unit tests
 
-  - name: notify coopcloud-dev on failure
+  - name: trigger downstream builds
+    image: plugins/downstream
+    settings:
+      server: https://drone.autonomic.zone
+      token:
+        from_secret: decentral1se_token
+      fork: true
+      repositories:
+        - coop-cloud/drone-abra
+    depends_on:
+      - run shellcheck
+      - run flake8
+      - run unit tests
+      - publish image
+
+  - name: notify on failure
     image: plugins/matrix
     settings:
       homeserver: https://matrix.autonomic.zone
@@ -45,6 +60,8 @@ steps:
       - run shellcheck
       - run flake8
       - run unit tests
+      - publish image
+      - trigger downstream builds
     when:
       status:
         - failure