feat+refactor: ability to skip some of the default checks

[shellwhale]

Pull Request

What? (description)

Define the default checks in a map instead of directly returning them in a slice.
Add a new function PreBootSequenceChecksFiltered to allow users to purposefully skip some checks.

Why? (reasoning)

While using the Terraform Talos Provider and a custom CNI (Cilium), if installing Cilium via Terraform (Terraform Helm Provider) (not doing it via the machine config file) the talos_cluster_health data source fails.

See siderolabs/terraform-provider-talos#206

This PR would allow to modify the Talos Terraform Provider (which use this package) in a way that would provide users with the ability to skip some of the checks defined in default.go, one of those checks would be "kubelet to be healthy" in the case of siderolabs/terraform-provider-talos#206.

Perhaps better names for each of the individuals checks in this new map[string]ClusterCheck would be suitable, or maybe another solution all together.

[smira]

as the package name is check, we can drop Check everywhere

[shellwhale]

Hello, is there something that I can do to complete this merge?

[smira]

Hello, is there something that I can do to complete this merge?

to address the review feedback?

[shellwhale]

@smira done

[smira]

@smira done

I don't see any changes, still everything is prefixed with Check, so it is check.Check*

[shellwhale]

@smira done

I don't see any changes, still everything is prefixed with Check, so it is check.Check*

I cannot do that because of

	case CheckAllNodesMemorySizes // Cannot drop the check word
		return func(cluster ClusterInfo) conditions.Condition {
			return conditions.PollingCondition(CheckAllNodesMemorySizes, func(ctx context.Context) error {
				return AllNodesMemorySizes(ctx, cluster) // Because it would result in the same name as this
			}, 5*time.Minute, 5*time.Second)
		}

[smira]

I cannot do that because of

probably these functions can be made private now? they should not be used outside of this package?

[shellwhale]

I cannot do that because of

probably these functions can be made private now? they should not be used outside of this package?

Maybe but this is pkg, not internal, so that would be a breaking change, is that what we want?

[smira]

I cannot do that because of

probably these functions can be made private now? they should not be used outside of this package?

Maybe but this is pkg, not internal, so that would be a breaking change, is that what we want?

Anyways it's a big change, so I'm ok with making it even bigger as long as it is consistent and bigger API