Expose batch subcommand

[gillg]

When you use the very usefull batch subcommand you can't use docker on npm wrapper.
https://openapi-generator.tech/docs/usage/#batch

NPM CLI Wrapper use help subcommand to validate possibles arguments https://github.com/OpenAPITools/openapi-generator-cli/blob/master/apps/generator-cli/src/app/services/pass-trough.service.ts#L21 so you get an error error: unknown command 'batch' when you use it.

In some cases, Docker image also could forbid usage of batch.

I will open a PR in https://github.com/OpenAPITools/openapi-generator-cli to propose usage of completion in place of help to check possible commands, but I think batch should no be hidden in help.

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[gillg]

Fixed in NPM Wrapper by @kay-schecker in OpenAPITools/openapi-generator-cli#44

Let see if we expose it in help or not...

[jimschubert]

Awesome. Thanks for hooking this up.

I think it makes a lot of sense. I'd written the batch command really only to speed up this project's builds, and was going to unhide if people showed interest. There's been a ton of interest and use of the command, so I think it should be officially exposed.