Live reload doesn't work inside docker

Everything works well: after editing a file backpack reloads an app.
But if I run in under the docker, and source files in a mounted folder - it doesn't work.
How I can fix it?

```
api:
build: ./api
volumes:
- ./api:/usr/app/
- /usr/app/node_modules
environment:
- SERVER_PORT=4000
- SERVER_HOST=0.0.0.0
- NODE_ENV=development
- DB_PORT=27017
- DB_HOST=mongo
- WAIT_HOSTS=mongo:27017
ports:
- "4000:4000"
expose:
- "4000"
links:
- mongo
working_dir: /usr/app
command: sh -c "/wait && yarn dev"
```

The reported setup is the Docker service configuration for `api`; start by reproducing it with the shown bind mount and `yarn dev`. Inspect how Backpack watches source files in this environment. Done means edits in the mounted `./api` source reliably trigger reload while the service runs in Docker.

Written by the indexing model from the issue text.