chore(deps): update circleci/node:8 docker digest to 9b19723

Author: renovate-bot

.circleci/config.yml

@@ -6,7 +6,7 @@ machine:
 jobs:
   build:
     docker:
-      - image: circleci/node:8@sha256:0e6beda8d9e1adb4b1ad6056213925f03285b90e8b652bcda925a25c45070d7d
+      - image: circleci/node:8@sha256:9b19723624c3144e92fd2fb358ea5a038a66ccc1dfcc585538b6a5b6658861c4
       - image: mongo:3.7.9@sha256:736eec20a17eafaa988d299902fcaab521cb0ca56af4400f782576afc878d6bc
     environment:
       - NPM_CONFIG_LOGLEVEL: warn