fix docker base image for circle ci

OpenGG · OpenGG · commit 2a51b3f9404b · 2017-11-20T13:59:17.000+08:00
diff --git a/.circleci/config.yml b/.circleci/config.yml
@@ -2,7 +2,7 @@ version: 2
 jobs:
   build:
     docker:
-      - image: debian:stable
+      - image: docker:stable
 
     steps:
       - checkout
