Fix mTLS values documentation

[dciangot]

[dciangot]

https://github.com/interlink-hq/interlink-helm-chart/blob/main/interlink/templates/virtual-kubelet.yaml#L65-L84

cert files are ready to be mounted here, but the doc in the main interlink repo is indicating another approach (with wrong values!)

Let's document the correct values here, then propagate this info to the main doc