There isn't much left to say, so we'll enter into the destructive mode and eliminate the cluster we created:
minikube delete
If you'd like to know more about Secrets, please explore Secret v1 core (https://v1-9.docs.kubernetes.io/docs/reference/generated/kubernetes-api/v1.9/#secret-v1-core) API documentation.
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Figure 10-1: The components explored so far