Upgrade to 4.1.5 and higher failed with "SchemaError(io.velero.v1.Restore.spec.hooks.resources.postHooks.init.initContainers): array should have exactly one sub-item"

[bmalynovytch]

What steps did you take and what happened:
Upgrade step by step from chart v2.13.5 to 5.0.2, ended failing at 4.1.5 with

SchemaError(io.velero.v1.Restore.spec.hooks.resources.postHooks.init.initContainers): array should have exactly one sub-item

What did you expect to happen:
Shouldn't fail / break upgrade

Related to vmware-tanzu/velero#6382

[aiici]

You can try to do it：

1. kubectl delete customresourcedefinitions.apiextensions.k8s.io restores.velero.io
2. kubectl delete customresourcedefinitions.apiextensions.k8s.io backuprepositories.velero.io
   If the first article is implemented and there is an error, the second article will be enforced

[jenting]

Have you try the above solution?