feat: Changes to controlplane spec should trigger a rollout

[wikoion]

This PR addresses #83, changes to the controlplane spec should trigger a rollout of controlplane machines.
I've tried to mirror the approach used in kubeadm as much as possible while adapting for k3s

[mogliang]

at least for controlplane, init and join cp node has same bootstrap config, this is different from how kubeadm works

cluster-api-k3s/pkg/k3s/control_plane.go

Lines 191 to 201 in 2a14b6e

	// InitialControlPlaneConfig returns a new KThreesConfigSpec that is to be used for an initializing control plane.
	func (c *ControlPlane) InitialControlPlaneConfig() *bootstrapv1.KThreesConfigSpec {
	bootstrapSpec := c.KCP.Spec.KThreesConfigSpec.DeepCopy()
	return bootstrapSpec
	}
	// JoinControlPlaneConfig returns a new KThreesConfigSpec that is to be used for joining control planes.
	func (c *ControlPlane) JoinControlPlaneConfig() *bootstrapv1.KThreesConfigSpec {
	bootstrapSpec := c.KCP.Spec.KThreesConfigSpec.DeepCopy()
	return bootstrapSpec
	}

I'm not very sure about worker node, you may provision a k3s cluster and check the bootstrap config.

Let's try if we can simplify this code

[wikoion]

Ah, I see what you mean. The init and join config is just the kcp KThreesConfigSpec, we do still compare this here, how do you suggest we should simplify the code?

[mogliang]

we can simply compare kcp config and machine bootstrap config directly, no need to compare serverConfig separately

[wikoion]

Addressed in the latest commit