Add comment for why /usr/bin is mounted

job-master.yaml

@@ -21,6 +21,8 @@ spec:
           mountPath: /var/lib/etcd
         - name: etc-kubernetes
           mountPath: /etc/kubernetes
+          # /usr/bin is mounted to access kubectl / kubelet, for auto-detecting the Kubernetes version. 
+          # You can omit this mount if you specify --version as part of the command.
         - name: usr-bin
           mountPath: /usr/bin
       restartPolicy: Never
@@ -33,4 +35,4 @@ spec:
           path: "/etc/kubernetes"
       - name: usr-bin
         hostPath:
-          path: "/usr/bin"
\ No newline at end of file
+          path: "/usr/bin"