How to Use TLS in Dask-Gateway?

I understand that it is recommended to use TLS in a production environment as per the docs, so I'm trying to set that up. Here are the steps I followed for my attempt at doing this:

[1] I added the paths to the self-signed certificate and key files in a Dockerfile
[2] Pushed that Docker Image to Google Cloud Image Repository
[3] Replace image names from "daskgateway/dask-gateway-server" to the image in Google Cloud Image Repo in the helm config file
[4] Added the paths to the self-signed key and cert files in the _extraConfig_ field

**What happened**:
Nothing changed. No errors. The internal load balancer for the traefik proxy server still using HTTP.

**What you expected to happen**:
I expected the internal load balancer to use HTTPS

**Minimal Complete Verifiable Example**:

Dockerfile:
```
FROM daskgateway/dask-gateway-server:latest

ADD certs /certs/
```

Helm Config:
```
extraConfig:
security: |
c.Proxy.tls_cert = "certs/myca.pem"
c.Proxy.tls_key = "certs/mykey.pem"
clusteroptions: |
from dask_gateway_server.options import Options, Integer, Float, String

c.KubeClusterConfig.idle_timeout = 3600

def option_handler(options):
return {
"worker_cores": options.worker_cores,
"worker_memory": "%fG" % options.worker_memory,
"image": options.image,
}

c.Backend.cluster_options = Options(
Integer("worker_cores", 2, min=1, max=8, label="Worker Cores"),
Float("worker_memory", 4, min=1, max=16, label="Worker Memory (GiB)"),
String("image", default="daskgateway/dask-gateway:latest", label="Image"),
handler=option_handler,
)
```

**Environment**:

- Helm version: 0.8.0