message: Include `help` in `--list`
diff: @@ -144,6 +144,14 @@ fn list_commands(config: &Config) -> BTreeMap<String, CommandInfo> {
  }
  }
  + // `help` is special, so it needs to be inserted separately.
  + commands.insert(
  + "help".to_string(),
  + CommandInfo::BuiltIn {
  + about: Some("Displays help for a cargo subcommand".to_string()),
  + },
  + );
  +
  commands
  }
  