change yml to yaml

clusters/default/system-upgrade/system-upgrade-plan.yml

@@ -1,42 +0,0 @@
-# Server plan
-apiVersion: upgrade.cattle.io/v1
-kind: Plan
-metadata:
-  name: server-plan
-  namespace: system-upgrade
-spec:
-  concurrency: 1
-  cordon: true
-  nodeSelector:
-    matchExpressions:
-    - key: node-role.kubernetes.io/control-plane
-      operator: In
-      values:
-      - "true"
-  serviceAccountName: system-upgrade
-  upgrade:
-    image: rancher/k3s-upgrade
-  channel: https://update.k3s.io/v1-release/channels/stable
----
-# Agent plan
-apiVersion: upgrade.cattle.io/v1
-kind: Plan
-metadata:
-  name: agent-plan
-  namespace: system-upgrade
-spec:
-  concurrency: 1
-  cordon: true
-  nodeSelector:
-    matchExpressions:
-    - key: node-role.kubernetes.io/control-plane
-      operator: DoesNotExist
-  prepare:
-    args:
-    - prepare
-    - server-plan
-    image: rancher/k3s-upgrade
-  serviceAccountName: system-upgrade
-  upgrade:
-    image: rancher/k3s-upgrade
-  channel: https://update.k3s.io/v1-release/channels/stable