✨ Upgrade CAPI to v0.4.0-beta.0

[sbueringer]

What this PR does / why we need it:
Update to current CAPI version before our own beta.0 release. Also went through the CAPI v1alpha3=>v1alpha4 migration doc again (https://github.com/kubernetes-sigs/cluster-api/blob/master/docs/book/src/developer/providers/v1alpha3-to-v1alpha4.md).

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Partially implements: #796

Special notes for your reviewer:

1. Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

TODOs:

• squashed commits
• if necessary:
  • includes documentation
  • adds unit tests

/hold

[chrischdi]

Looks like there's a different binary used in make generate.

/lgtm

[sbueringer]

Looks like there's a different binary used in make generate.

/lgtm

Thx, fixed, ptal :)

[sbueringer]

Had to fix the cluster templates. There is a breaking change in KubeadmControlPlane (just another reason why v1alpha3 is not really compatible with v1alpha4, which is intended)

[jichenjc]

generally looks good
let's wait for e2e test

[sbueringer]

@hidekazuna thx, ptal :)
@jichenjc last findings fixed. tests have been green once. I would like to merge relatively soon after the tests are green again after the last fixes.

[hidekazuna]

/lgtm

[jichenjc]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jichenjc, sbueringer

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[sbueringer]

/hold cancel