Update OkHttp to 5.x

[hantsy]

Checklist

• I have looked into the Readme and Examples, and have not found a suitable solution or answer.
• I have looked into the API documentation and have not found a suitable solution or answer.
• I have searched the issues and have not found a suitable solution or answer.
• I have searched the Auth0 Community forums and have not found a suitable solution or answer.
• I agree to the terms within the Auth0 Code of Conduct.

Describe the problem you'd like to have solved

Currently some OkHttp deps of third party libs in my project are upgraded to 5.x (5.0.0.Alpha14), which will break the APIs in the auth0-java which used an old Okhttp.

Describe the ideal solution

I would like there is a new branch for the future development, and also upgrade the code style and code base to modern java that align with the popular frameworks.

• Upgrade codes to Java 17.
• Upgrade OkHttp to 5.x
• Add ReactiveStreams/Java 9 Flow.Publisher and Kotlin Coroutines support.

Alternatives and current workarounds

No response

Additional context

No response