Newtonsoft.Json Dependency is not performant

[jonatr35]

It is well documented that newtonsoft.json is not performant and is not ideal for any cloud serverless applications. This does not seem like a very difficult change to make and would help with anyone using this package in a serverless application. There is even support to have github copilot migrate for you:

https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/migrate-from-newtonsoft?pivots=dotnet-8-0#use-github-copilot-to-migrate

https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/migrate-from-newtonsoft?pivots=dotnet-8-0

Thanks!

[jonatr35]

Looks like it would have to be removed from this contentstack-dotnet dependency: https://github.com/contentstack/contentstack-utils-dotnet