Add preflight network resource support for custom_cni

[HoKim98]

PR Type

/kind feature

What this PR Does / Why We Need It

• Enables the deployment of network resources such as CRDs prior to CNI

Which Issue(s) this PR Fixes

Fixes #

Special Notes for Your Reviewer

I want to enable the serviceMonitor option when installing Cilium CNI as custom_cni. However, I couldn't find a way to deploy the ServiceMonitor CRD prior to CNI installation. So I want to add a feature to deploy the prerequisite resources that should be deployed before the CNI during the custom_cni deployment process.

Additionally, I have prepared a new PR to enable pre-deployment of Ansible Roles if the pre-deployment feature for resources is merged in any form (custom_cni, generic, ...). This was necessary because while deploying Cilium CNI, I encountered an issue where the deployment of hubble-relay failed due to CoreDNS not being active when the peer service was enabled on cilium-agent. This PR aims to address that problem.

Does this PR Introduce a User-Facing Change?

No, this new method is managed by new variable custom_cni_preflight_templates.

Add preflight network resource support for custom_cni: `custom_cni_preflight_templates`

[k8s-ci-robot]

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[k8s-ci-robot]

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[ant31]

is the namespace also set to kube-system in other cni/network plugin deployments?

[HoKim98]

Hardcoding the namespace is definitely not appropriate. Therefore, I have modified and rebased the code to allow setting the namespace in the ".namespace" format! However, generally, CNIs are deployed in the kube-system namespace. Thus, if the namespace is not specified, I have adjusted it to use kube-system as the default.

[ant31]

/ok-to-test

[tico88612]

I think it's a nice feature, but I don't think it needs to be limited to custom_cni?

[HoKim98]

I agree that using the CNI deployment method managed by Kubespray, as in the case of custom_cni, would be convenient for users. However, I am concerned that this might prevent the development of pre-deployment features that many might need, by providing a new workaround for users to solve issues themselves instead of reporting them to the community. If this concern of mine is unfounded (or not something I should worry about), I am willing to modify the code to apply it to all CNIs!