Retrieves a list of subscription definitions.Show details from next link. https://docs.aws.amazon.com/ja_jp/cli/latest/reference/greengrass/list-subscription-definitions.html
| aws greengrass list-subscription-definitions \ |
| CreateSubscriptionDefinitionVersionRequestBody - AWS Greengrass : http://docs.aws.amazon.com/greengrass/latest/apireference/-greengrass-definition-subscriptions.html |