The container machineset-controller is stuck in CrashLoopBackOff status during upgrade to Openshift Container Platform 4.7.0

Issue

The upgrade is stuck as "machine-api" can not progress:

2021-03-02T09:34:14.748259861Z E0302 09:34:14.748247       1 task.go:112] error running apply for clusteroperator "machine-api" (166 of 668): Cluster operator machine-api is still updating
2021-03-02T09:34:14.748351866Z I0302 09:34:14.748338       1 task_graph.go:555] Result of work: [Cluster operator machine-api is still updating]
2021-03-02T09:34:14.748369434Z I0302 09:34:14.748357       1 sync_worker.go:937] Update error 166 of 668: ClusterOperatorNotAvailable Cluster operator machine-api is still updating (*errors.errorString: cluster operator machine-api is still updating)
2021-03-02T09:34:14.748398918Z E0302 09:34:14.748386       1 sync_worker.go:353] unable to synchronize image (waiting 2m50.956499648s): Cluster operator machine-api is still updating