Update '.drone.yml'

.drone.yml

@@ -2,6 +2,22 @@
 kind: pipeline
 type: docker
 name: default
+platform:
+  arch: arm64
+
+steps:
+- name: firststep
+  image: alpine
+  commands:
+  - echo hello world
+  - cat README.md
+
+---
+kind: pipeline
+type: docker
+name: default
+platform:
+  arch: amd64
 
 steps:
 - name: firststep