✨ Support RKE2ControlPlane mhc remediation

[MaxFedotov]

kind/feature

What this PR does / why we need it:

This PR adds support for RKE2ControlPlane remediation. The code is taken from KCP (https://github.com/kubernetes-sigs/cluster-api/blob/main/controlplane/kubeadm/internal/controllers/remediation.go) and adopted for RKE2. It also adds a new rcp_remediation_test e2e test, based on CAPI e2e KCPRemediationSpec.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #626

Special notes for your reviewer:

Checklist:

• squashed commits into logical changes
• includes documentation
• adds unit tests
• adds or updates e2e tests

[furkatgofurov7]

Hey, thanks for the PR 👍🏼
I have not looked into the logic yet, but can you please first rename the KCP mentions with RKE2ControlPlane everywhere (comments, file names, vars etc)?

[MaxFedotov]

Hey @furkatgofurov7, done. The only place where i left kcp is in tests, because i've used the standard capi KCPRemediationSpec test

[furkatgofurov7]

@MaxFedotov you can run make lint locally to make sure lint CI passes here

[MaxFedotov]

@furkatgofurov7, done

[MaxFedotov]

hey @furkatgofurov7! Is there anything else i can do to proceed with this PR? Thanks!

[MaxFedotov]

Sorry for the force push, had to rebase the branch to the latest main to fix the conflicts

[MaxFedotov]

@furkatgofurov7 done, changes in makefile and dockerfile rollbacked

[furkatgofurov7]

@MaxFedotov thanks for patience and taking a time to address the review comments. This change LGTM, can you please squash the commits as much as needed to avoid duplicate commit messages to have a logically coherent commit flow? Thanks!

[MaxFedotov]

@furkatgofurov7 done!

[MaxFedotov]

@furkatgofurov7 looking on the test error and the cluster-api code, template name should be cluster-template-kcp-remediation.yaml because it also depends on the hardcoded specName variable - https://github.com/kubernetes-sigs/cluster-api/blob/main/test/e2e/kcp_remediations.go#L93

I will make a commit with rename, can we try to run the tests using the cluster-template-kcp-remediation.yaml?

[MaxFedotov]

All tests green, great :)

[furkatgofurov7]

Great work, thanks for the PR!