Dagster Cloud has introduced a new and improved way to manage secrets, specifically environment variables, making it easier for users to securely authenticate with external services without having to hard-code credentials or insecurely store sensitive data. The new feature allows users to set up environment variables within the Dagster Cloud UI, which are then automatically included in their code execution. Additionally, users can create different scopes for environment variables, from local development to production, and access them in their code using various methods such as directly accessing the environment variable or referencing it in the config system. The feature also utilizes Amazon Key Management Services (KMS) and envelope encryption to securely store environment variables defined using the Dagster Cloud UI.