update Drone CI configuration

.drone.yml

@@ -1,15 +1,7 @@
 kind: pipeline
 name: default
 
-clone:
-  disable: true
-
 steps:
-- name: clone
-  image: plugins/git
-  settings:
-    depth: 10
-    skip_verify: true
   - name: pre-build
     image: composer
     commands:
@@ -17,8 +9,8 @@ steps:
   - name: test
     image: composer
     commands:
-  - ./vendor/bin/robo test
+      - composer test
-- name: test-style
+  - name: lint
     image: composer
     commands:
-  - ./vendor/bin/robo test:cs
+      - composer lint-php