Update '.drone.yml'

.drone.yml

@@ -2,9 +2,9 @@
 kind: pipeline
 name: docker-json-validate build
 
-steps:
-- name: docker  
-  image: plugins/docker
+pipeline:
+  docker:
+    image: woodpeckerci/plugin-docker-buildx
     settings:
       repo: git.freifunk-rhein-sieg.net/freifunk-troisdorf/docker-json-validate
       registry: git.freifunk-rhein-sieg.net
@@ -12,11 +12,13 @@ steps:
       from_secret: docker_username
     password:
       from_secret: docker_password
-- name: validate json good
+
+  validate_good:
     image: fftdf/docker-json-validate
     commands:
       - jsonlint test_val.json
-- name: validate json bad
+      
+  validate_bad:
     image: fftdf/docker-json-validate
     commands:
       - jsonlint test_not_val.json