Error 401 (Unauthorized)

### What version of `ReactiveSearch API` are you using ?

Lastest

### What issue did you run into?

When configuring a remote elasticsearch the variables found in config/docker.env (username and password) don't work, I had to put the credentials in the url. Is there a way to not have to pass the credentials through the url?

### What did you expect to see?
```bash
ES_CLUSTER_URL=https://my-elastic.com
USERNAME=username
PASSWORD=password
```

### What did you see instead?
```bash
ES_CLUSTER_URL=https://username:password@my-elastic.com
```