[BUG] Incorrect kubectl command on upgrading a tenant

[marktheunissen]

Describe the bug

This page: https://min.io/docs/minio/kubernetes/upstream/operations/install-deploy-manage/upgrade-minio-tenant.html

Has a step where we run kubectl apply -f ./ on a kustomize directory.

The kubectl apply command with -f is for a file, however we are running it on a directory in which we just dropped a new kustomization.yaml file, so the correct command is kubectl apply -k ./*

Reported and tested by a customer.

I'm not sure if the trailing * is necessary, I suspect it is not, however that's what was successfully run by the customer