I am using Kotlin with Vertx at the Backend and the frontend forwards me a JWT token after getting authenticated from One Login. Now, I want to make sure that the Token is valid not fake(made up). If I follow following link, it says that I need a public key to be able to create a JWTAuth object which I can use to call authenticate for validation.
<https://vertx.io/docs/vertx-auth-jwt/kotlin/>

I need to know where can I get public key?