'whalesay' does not support arm64 and should not use as an example for the book

[zoltan-tarko]

As 'whalesay' does not support arm64, it blocks the learning right in the beginning. Especially true, if the given person (as myself) does not have experience with minikube/kubernetes and this architecture previously.

It would be the best if a different example would be used, considering the compatibility with arm64 as well. Unfortunately I don't have a proposal, because I just started to learn minikube/kubernetes and gitops.