This will allow you to subscribe a lead to any specific mailing list. Note that you must have previously created your list within your Kartra account (https://app.kartra.com/communication/lists).
The API call will fail if it doesn’t find the specified list within your Kartra account.
* Required fields
Here is an example:
'actions' => [ '0' => [ 'cmd' => 'subscribe_lead_to_list', 'list_name' => 'List name' ] ]