rollback command help indicates accepting a file

I installed pgroll via Homebrew:
```
$ pgroll --version
pgroll version 0.10.0
```

The inline help indicates accepting a file
```
$ pgroll rollback --help
Roll back an ongoing migration

Usage:
  pgroll rollback <file> [flags]
...
```

I suppose it shouldn't, the online documentation doesn't mention it: https://pgroll.com/docs/latest/cli/rollback
