captionAsset.serve and captionAsset.serveAsJson do not exist as a function

[LluisJP]

We are using the node js version of this package in our company to interact with kaltura and we wanted to obtain the captions of specific videos(using captionAsset.list as an intermediate step).
From what we've seen in the api docs there are 2 different endpoints that do this:

1. https://developer.kaltura.com/api-docs/service/captionAsset/action/serveAsJson
2. https://developer.kaltura.com/api-docs/service/captionAsset/action/serve

But when we used them it said that they do not exist as a function. I looked at the kalturaServices.js in the node modules and indeed this functions do not exists, we can use the getUrl to get a download link but if possible we would prefer a more direct action, specially since they appear in the api docs.