Add identity-base integration to documentation (#1)

[vpetroff]

Added a new integration for identity-base that simplifies user management with OpenIddict.

[Copilot]

Pull Request Overview

This PR adds documentation for a new integration called "identity-base" that simplifies user management with OpenIddict. The integration is positioned as a drop-in solution that handles user database setup, OIDC flows, and common user workflows while allowing developers to bring their own UI.

• Adds identity-base integration to the community integrations list

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[Copilot]

[nitpick] The description is too verbose and informal for documentation. Consider shortening it to focus on key features: 'A drop-in NuGet package that provides pre-configured user management including registration, authentication flows, MFA, and social logins with OpenIddict integration. Includes ReactJS components for frontend integration.'

Suggested change

- **[identity-base](https://github.com/Amaretto-Software-Labs/identity-base)** by [Amaretto Software Labs](https://github.com/Amaretto-Software-Labs): tired of setting up AspNet Identity, OpenIddict, user db, all the user flows including user registration, confirm email, forgot password, MFA, social logins? Identity Base is drop-in nuget package that handles all the complexities - you bring your UI, Identity Base handles the user db and OIDC flows through OpenIddict. Even comes with its own ReactJS package to make it easy to integrate into your ReactJS frontends.

- **[identity-base](https://github.com/Amaretto-Software-Labs/identity-base)** by [Amaretto Software Labs](https://github.com/Amaretto-Software-Labs): A drop-in NuGet package that provides pre-configured user management including registration, authentication flows, MFA, and social logins with OpenIddict integration. Includes ReactJS components for frontend integration.

[kevinchalet]

Thanks for your PR! Copilot listed a few recommendations that seem valid to me so PTAL when you have a moment.

Note: your description mentions "AspNet Identity", which refers to the OWIN version of Identity (for the "legacy" ASP.NET 4.x, basically). Consider using "ASP.NET Core Identity" instead.

[vpetroff]

Thanks for pointing that out, I've refined the description to be more precise and reworded it as per Copilot's recommendation.