Add missing quotes for interceptor's TLS-related env vars

[jkremser]

The env vars were not quoted which ended up in ports not being quoted and helm chart was not installable.

 {{ .. | quote }}

.. would also work, but this way it's consistent w/ the other variables in this file

Checklist

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Reproduction of the issue, this pr fixes:

helm upgrade -i http-add-on . --namespace keda  --set crds.install=false --set interceptor.tls.enabled=true
Release "http-add-on" does not exist. Installing it now.
Error: 1 error occurred:
	* Deployment in version "v1" cannot be handled as a Deployment: json: cannot unmarshal number into Go struct field EnvVar.spec.template.spec.containers.env.value of type string

[zroubalik]

LGTM, thanks!