Issue with `DefaultHelpTextGenerator` in `GenerateCommands`

[hugoqribeiro]

GenerateCommands in DefaultHelpTextGenerator does not handle commands correctly when there are multiple levels of subcommands.

To Reproduce

Steps to reproduce the behavior:

1. Version 4.0.1
2. Define more than one level of subcommands.
3. Execute with arguments: command1 command2 --help
4. The help text under Run 'XXX' for more information about a command does not enumerate the commands correctly.

Outputs

Notice the output from the following command line...

li service spec --help

Commands concerning service specifications.

Usage: li service spec [command] [options]

Options:
  --help  Display help information.

Commands:
  merge   Merge two or more service spec files.

Run 'spec [command] --help' for more information about a command.

It should be:

Run 'li service spec [command] --help' for more information about a command.