[liqoctl] fix help commands templating

[claudiolor]

Description

This PR fixes the templating of the liqoctl help messages. Some of the commands templates were not filled, as in the example below:

Generate the Tenant resource to be applied on the remote provider cluster.

This commands generates a Tenant filled with all the authentication parameters needed to authenticate with the remote cluster.
It signs the nonce provided by the remote cluster and generates the CSR.
The Nonce can be provided as a flag or it can be retrieved from the secret in the tenant namespace (if existing).

Examples:
  $ {{ .Executable }} generate tenant --remote-cluster-id remote-cluster-id

This PR fixes this issue by wrapping the Cobra AddCommand function, so that when the wrapper function is called, the help messages templates are automatically filled.

[adamjensenbot]

Hi @claudiolor. Thanks for your PR!

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• feat: 🚀 New Feature
• fix: 🐛 Bug Fix
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