feat: add OIDC Riot Games provider

[Jorgagu]

Title of the Pull Request

feat: add OIDC Riot Games provider

Description of the Pull Request

This pull request introduces a new OIDC provider for Riot Games to the Ory Kratos project. This feature allows users to authenticate using their Riot Games account, expanding the range of supported OIDC providers and improving the flexibility of authentication options within Ory Kratos.

• Riot Games: A popular gaming platform with millions of users, making this integration valuable for gaming-related applications.
• OIDC Integration: This provider follows the standard OIDC implementation, ensuring secure and reliable authentication.

Related issue(s)

Checklist

• I have read the contributing guidelines.
• I have referenced an issue containing the design document if my change
  introduces a new feature.
• I am following the contributing code guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
  vulnerability. If this pull request addresses a security vulnerability, I
  confirm that I got the approval (please contact
  [email protected]) from the maintainers to push
  the changes.
• I have added tests that prove my fix is effective or that my feature
  works.
• I have added or changed the documentation.

Further Comments

This feature was chosen to support the growing number of gaming-related applications that rely on Riot Games for user authentication. The implementation follows standard practices for OIDC providers in Ory Kratos, ensuring compatibility and ease of use. At GameVerse, we're already using it in a customized version of Kratos based on version v1.1.0 and this OIDC provider.

[Jorgagu]

@aeneasr @vinckr @hperl @zepatrik How can I assist you in reviewing and merging this pull request?