[Bug] docfx -? lists arguments in wrong order: [config] [OPTIONS] [COMMAND]

**Describe the bug**

Command line help prints this:
```
USAGE:
    docfx [config] [OPTIONS] [COMMAND]
```

**To Reproduce**

Run:
`docfx -?`

**Expected behavior**

Usage should print the correct order with [COMMAND] as the first item:

```
USAGE:
    docfx [COMMAND] [config] [OPTIONS]
```

**Context (please complete the following information):**
- OS: Windows
- Docfx version: 2.78.5
