Add Logto to Authentication and Authorization

Logto is an open-source Auth0, Cognito and Firebase auth alternative for modern apps and SaaS products, supporting OIDC, OAuth 2.0 and SAML open standards for authentication and authorization.

Logto supports dedicated .NET SDKs: https://docs.logto.io/quick-starts

GitHub: https://github.com/logto-io/logto
Website: https://logto.io
Docs: https://docs.logto.io

Author: Rany0101

README.md

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