Update K8s versions and container runtime

examples/preflight/sample-preflight.yaml

@@ -7,15 +7,15 @@ spec:
     - clusterVersion:
         outcomes:
           - fail:
-              when: "< 1.13.0"
-              message: This application requires at least Kubernetes 1.13.0 or later, and recommends 1.15.0.
+              when: "< 1.20.0"
+              message: This application requires at least Kubernetes 1.20.0, and recommends 1.22.0.
               uri: https://www.kubernetes.io
           - warn:
-              when: "< 1.15.0"
-              message: Your cluster meets the minimum version of Kubernetes, but we recommend you update to 1.15.0 or later.
+              when: "< 1.22.0"
+              message: Your cluster meets the minimum version of Kubernetes, but we recommend you update to 1.22.0 or later.
               uri: https://kubernetes.io
           - pass:
-              when: ">= 1.15.0"
+              when: ">= 1.22.0"
               message: Your cluster meets the recommended and required versions of Kubernetes.
     - customResourceDefinition:
         checkName: Ingress
@@ -28,10 +28,10 @@ spec:
     - containerRuntime:
         outcomes:
           - pass:
-              when: "== docker"
-              message: Docker container runtime was found.
+              when: "== containerd"
+              message: containerd container runtime was found.
           - fail:
-              message: Did not find Docker container runtime.
+              message: Did not find containerd container runtime.
     - storageClass:
         checkName: Required storage classes
         storageClassName: "default"
@@ -121,4 +121,4 @@ spec:
             message: All nodes are recommended to have at least 100 GB of ephemeral storage.
             uri: https://kurl.sh/docs/install-with-kurl/system-requirements
         - pass:
-            message: All nodes have at least 100 GB of ephemeral storage.
+            message: All nodes have at least 100 GB of ephemeral storage.