A company has an application that uses an Amazon Aurora PostgreSQL DB cluster for the application's database. The DB cluster contains one small primary instance and three larger replica instances. The application runs on an AWS Lambda function. The application makes many short-lived connections to the database's replica instances to perform read-only operations. During periods of high traffic, the application becomes unreliable and the database reports that too many connections are being established. The frequency of high-traffic periods is unpredictable. Which solution will improve the reliability of the application?