🐛 Mitigate managedFields apiserver issue for SSA

[sbueringer]

What this PR does / why we need it:

Through an issue in kube-apiserver (kubernetes/kubernetes#136919) it can happen that managedFields of objects are dropped.

This is problematic for cases where core CAPI is using SSA to continuously update objects.

This PR mitigates this issue by restoring managedFields for all cases where we use SSA.

Once the issue is fixed in kube-apiserver and our min supported version matches accordingly we can remove this code again.

The following objects are affected:

For classy clusters:

• Cluster
• InfraCluster
• ControlPlane
• MachineDeployment, MachinePool, MachineHealthCheck
• BootstrapConfigTemplate, InfraMachineTemplate
• BootstrapConfig, InfraMachinePoolTemplate

For all clusters:

• MachineSets
• Machines, BootstrapConfig, InfraMachine (managed by KCP + MS)

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 #

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[sbueringer]

/test pull-cluster-api-e2e-main-gke

[sbueringer]

/test pull-cluster-api-e2e-main-gke

[k8s-ci-robot]

@sbueringer: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-cluster-api-e2e-main-gke	11817f5	link	true	/test pull-cluster-api-e2e-main-gke

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[sbueringer]

I was thinking about getting rid of getAndAdoptMachinesForMachineSetSucceeded (and the same field in the MD controller) in a follow-up. But we cannot do that because there is still code that has to check for it