Allow users to enable host network in Kubewarden resources

[jvanz]

Recently we received a request from users to allow them to run Kubewarden resources with host network enabled. After some deliberation and looking for another solutions for the user issue, we've agreed on that the only solution that we, the Kubewarden team, can do is to give users the power to enable host network. All other possible solutions for this issue is out of control of the Kubewarden project and involves changes in users infrastructure.

As this configuration can increase the attack surface, this feature should be disable by default. And it should be well documented explaining the risks for users.

Acceptance criteria

• Update the admission controller reconciliation loop to configure policy server deployments enabling host network when requested by user
• Update Helm chart to allow users to enable host network when deploying admission controller
• Add tests to cover this new feature