Update config.yml

.circleci/config.yml

@@ -7,5 +7,8 @@ jobs:
           username: mydockerhub-user
           password: $DOCKERHUB_PASSWORD  # context / project UI env-var reference
     steps:
+    - restore_cache:
+         keys:
+           - npm-v1-dependencies-{{ checksum "yarn.lock" }}
       - checkout # check out the code in the project directory
-      - run: echo "hello world" # run the `echo` command
+      - run: yarn install