[TD-629] Allow multiple container ports in hybrid

[jbiskur]

Currently, there is no way of adding more container ports for the gateways whitelisting of ports feature as the "ports:
- containerPort: {{ .Values.gateway.containerPort }}" in the "tyk-hybrid/templates/deployment-gw-repset.yaml only accepts a single value rather than an array.

It would be solved by having:
gateway:
containerPort:
- 8443
- 2223
- 2224

extraEnvs:
- name: "TYK_GW_PORTSWHITELIST_PORTSWHITELIST_TCP_PORTS"
value: "2223,2224"

[n2linux]

Howdy @jbiskur - thanks for opening this issue! We will take a look and get this added to our internal feature request list.