kebyn

[官方文档]( https://kubernetes.io/docs/tasks/inject-data-application/define-command-argument-container/#use-environment-variables-to-define-arguments)有解释，需要使用$(VAR)，而不是${VAR}引用变量
```
Note: The environment variable appears in parentheses, "$(VAR)". This is required for the variable to be expanded in the command or args field.
```