Prevent upgrades of managed topologies while previous upgrade is not yet completed

[ykakarap]

What steps did you take and what happened:
If the topology version is upgraded to v2 while the cluster is in the middle of upgrading from v0 to v1 the control plane will eventually pick up v2 after upgrading to v1 before the Machine Deployments have been upgraded to v1.

This will lead to machine deployments being eventually upgraded from v0 to v2, skipping v1 entirely.

What did you expect to happen:

The upgrade of v1 should be completely done before the cluster starts upgrading to v2.

Anything else you would like to add:
[Miscellaneous information that will assist in solving the issue.]

Environment:

• Cluster-api version: main
• Minikube/KIND version:
• Kubernetes version: (use kubectl version):
• OS (e.g. from /etc/os-release):

/kind bug
[One or more /area label. See https://github.com/kubernetes-sigs/cluster-api/labels?q=area for the list of labels]

/area topology

[ykakarap]

/assign

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/lifecycle stale

[ykakarap]

/lifecycle frozen