enable fossa scanning

request: https://github.com/rancherlabs/eio/issues/772

.drone.yml

@@ -373,3 +373,17 @@ depends_on:
 - s390x
 - arm64
 - arm
+
+---
+kind: pipeline
+name: fossa
+
+steps:
+- name: fossa
+  image: rancher/drone-fossa:latest
+  settings:
+    api_key:
+      from_secret: FOSSA_API_KEY
+    when:
+      instance:
+        - drone-publish.rancher.io