message: add mongodb data volume mount
diff: @@ -6,6 +6,8 @@ services:
  hostname: mongo
  ports:
  - 27017:27017
  + volumes:
  + - mongo-data-volume:/data/db
  nodeosd:
  image: eosio/eos:latest
  @@ -31,6 +33,8 @@ services:
  - keosd-data-volume:/opt/eosio/bin/data-dir
  volumes:
  + mongo-data-volume:
  + external: true
  nodeos-data-volume:
  external: true
  keosd-data-volume:
  