ingress-controller chart: Gateway service not listening on https port

Enabling TLS on the `ingress-controller` gateway service (`apisix-ingress-controller-apisix-gateway`) doesn't make the pod listen on port 9443.

This causes refused connections since the LoadBalancer's public IP doesn't have anywhere to connect:
```
curl: (7) Failed to connect to test-apisix.example.com port 443 after 262 ms: Connection refused
```

Configured `ingress-controller` as an `apisix` subchart, but the same applies for the standalone chart:
```
ingress-controller:
enabled: true
config:
# misconfig due to a hardcoded value https://github.com/apache/apisix-helm-chart/issues/774
httpListen: ":9080"
ingressPublishService: "ingress-apisix/apisix-ingress-controller-apisix-gateway"
apisix:
adminAPIVersion: "v3"
existingSecret: "admin-creds"
existingSecretAdminKeyKey: "admin"
gateway:
type: LoadBalancer
externalTrafficPolicy: Local
tls:
enabled: true <== DOESN'T WORK
```

Only the HTTP port (9080) is specified in the `deployment.yaml` [template](https://github.com/apache/apisix-helm-chart/blob/master/charts/apisix-ingress-controller/templates/deployment.yaml#L97-L99) and there's no optional setting for the TLS port like the `apisix` chart's [template](https://github.com/apache/apisix-helm-chart/blob/master/charts/apisix/templates/deployment.yaml#L111).

The only place that the `tls` key is used is in the `etcd` server sidecar [here](https://github.com/apache/apisix-helm-chart/blob/master/charts/apisix-ingress-controller/templates/deployment.yaml#L147), which also looks a bit mistakenly copied.

Start by rendering the ingress-controller chart and inspect charts/apisix-ingress-controller/templates/deployment.yaml around the HTTP container port and the etcd sidecar TLS reference. Compare it with charts/apisix/templates/deployment.yaml, then verify that enabling gateway TLS causes the pod and service to expose and listen on port 9443.

Written by the indexing model from the issue text.