fix custom resource name for eksaVersion

[sotoiwa]

Issue #, if available:

Description of changes: EKSARelease is the correct custom resource name and there is no resource named eksaVersion. eksaVersion is a field in the cluster spec file.

$ kubectl api-resources  | grep -i eksa
eksareleases                                     anywhere.eks.amazonaws.com/v1alpha1       true         EKSARelease

Testing (if applicable):

Documentation added/planned (if applicable):

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.