"Cannot get connection id for node" error during start up

[unnawut]

Describe the bug
"Cannot get connection id for node ewallet@..." error is logged during application start up.

Thanks to @hiremu for bringing this up to our attention.

To Reproduce
Steps to reproduce the behavior:

1. Follow the getting started instructions on README.md
2. The application starts up fine, however with the "Cannot get connection id for node ewallet@..." as seen in the log below.

$ curl -O -sSL https://raw.githubusercontent.com/omisego/ewallet/master/docker-compose.yml
...
$ curl -O -sSL https://raw.githubusercontent.com/omisego/ewallet/master/docker-gen.sh
...
$ chmod +x docker-gen.sh
...
$./docker-gen.sh > docker-compose.override.yml
...
$ docker-compose run --rm ewallet initdb
...
$ docker-compose run --rm ewallet seed
...
$ docker-compose up -d
...

$ docker-compose logs ewallet
Attaching to ewallet-reyeshh_ewallet_1
ewallet_1   | [s6-init] making user provided files available at /var/run/s6/etc...exited 0.
ewallet_1   | [s6-init] ensuring user provided files have correct perms...exited 0.
ewallet_1   | [fix-attrs.d] applying ownership & permissions fixes...
ewallet_1   | [fix-attrs.d] done.
ewallet_1   | [cont-init.d] executing container initialization scripts...
ewallet_1   | [cont-init.d] done.
ewallet_1   | [services.d] starting services
ewallet_1   | [services.d] done.
ewallet_1   | 04:20:25.969 [info] AppSignal disabled.
ewallet_1   | 04:20:25.976 [info] [swarm on ewallet@f153258b265c] [tracker:init] started
ewallet_1   | 04:20:26.478 [error]
ewallet_1   | ** Cannot get connection id for node :ewallet@f153258b265c
ewallet_1   |
ewallet_1   | 04:20:30.270 [info] tzdata release in place is from a file last modified Tue, 26 Mar 2019 05:40:14 GMT. Release file on server was last modified Mon, 01 Jul 2019 16:50:25 GMT.
ewallet_1   | 04:20:30.977 [info] [swarm on ewallet@f153258b265c] [tracker:cluster_wait] joining cluster..
ewallet_1   | 04:20:30.977 [info] [swarm on ewallet@f153258b265c] [tracker:cluster_wait] no connected nodes, proceeding without sync
ewallet_1   | 04:20:30.992 [info] Running UrlDispatcher.Plug with Cowboy on port 4000.
ewallet_1   | 04:20:30.992 [info] Running EWalletAPI.V1.Endpoint WebSocket endpoint at /api/client/socket.
ewallet_1   | 04:20:30.992 [info] Running AdminAPI.V1.Endpoint WebSocket endpoint at /api/admin/socket.
ewallet_1   | 04:20:34.297 [info] Tzdata has updated the release from 2019a to 2019

Expected behavior
The application should start without the connection error.

Additional context
This should only affect running the eWallet as a cluster.