[SDK-4652] Spring Boot Login - Use Spring Boot 3 and Okta Spring Boot Starter

[jimmyjames]

Changes

Updates the quickstart to use latest Spring Boot and the Okta Spring Boot Starter.

This change accompanies auth0-samples/auth0-spring-boot-login-samples#21

[mraible]

Are these variables that are replaced? Otherwise, the syntax looks funny.

[frederikprijck]

Yes account.namespace becomes the domain, and account.clientId the corresponding clientId based on the selected application when logged in in the docs platform. When not logged in, these gets replaced by placeholders.

For example, see the already existing quickstart for spring-boot: https://github.com/auth0/docs/blob/master/articles/quickstart/webapp/java-spring-boot/files/application.md

When not logged in, these become:

spring:
  security:
    oauth2:
      client:
        registration:
          auth0:
            client-id: {yourClientId}
            client-secret: YOUR_CLIENT_SECRET
            scope:
              - openid
              - profile
              - email
        provider:
          auth0:
            # trailing slash is important!
            issuer-uri: https://{yourDomain}/

While when logged in, they reflect actual values. This allows to easily copy paste the config when being logged in to the docs platform, while avoiding the weird syntax when not being logged in (because yeah, the syntax is not something that makes sense for our users, but it should also be something our users won't ever see)

As you can see, it's a bit different for the secret, as we don't ever prefill secrets afaik.

[jimmyjames]

@mraible yes, they are replaced when a user logs in and downloads the sample.