chore(deps): update node:8.16.0 docker digest to ee7adf8

Author: renovate-bot

.circleci/config.yml

@@ -6,7 +6,7 @@ machine:
 jobs:
   build:
     docker:
-      - image: node:8.16.0@sha256:51e3a82bc141a4646b86acc76f52b7c2ef72a5050d97788cc0bd41e029f0d711
+      - image: node:8.16.0@sha256:ee7adf8240cd6e06d96b459c69a7900bd8a044accc74ee2f3ae7d432c8d034e5
     environment:
       - NPM_CONFIG_LOGLEVEL: warn
     working_directory: ~/repo