fix: liqoctl cluster labels and API server addr override collection

[claudiolor]

Description

The liqoctl info command returns a waning everytime:

• the Liqo intallation has no cluster labels: but this is acceptable
• the K8s api server address is overwritten: as no API server address is found. The info command does not handle the case in which there is an override of the K8s API server address, so the output does not show the correct address.

This PR fixes this issue by not issuing any warning when labels are not found and by checking on the controller-manager if an override of the K8s API server has been configured.

[adamjensenbot]

Hi @claudiolor. Thanks for your PR!

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