switched to custom clone logic

ref #23

.drone.yml

@@ -2,13 +2,13 @@
 kind: pipeline
 name: tests:latest
 clone:
-  branch: $DRONE_SOURCE_BRANCH
+  disable: true
 steps:
-# - name: checkout pr
-#   image: alpine/git
-#   commands:
-#   - git clone $DRONE_REMOTE_URL
-#   - git checkout 
+- name: checkout pr
+  image: alpine/git
+  commands:
+  - git clone $DRONE_REMOTE_URL
+  - git checkout $DRONE_SOURCE_BRANCH
 - name: run tests
   image: node:alpine
   commands: