Create table of System.Text.Json - Newtonsoft.Json equivalents

[tdykstra]

Related to #12207 and #14446

Create table of equivalents as a quick-reference section for the Migrate from Newtonsoft.Json article, per PR comment by pranavkm.

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Document Details

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• ID: 6b74d77c-33e1-d44c-18c6-bd0b612f74de
• Version Independent ID: 9c6a7135-eb75-21a9-1d27-0880459523ca
• Content: Migrate from Newtonsoft.Json to System.Text.Json - .NET
• Content Source: docs/standard/serialization/system-text-json-migrate-from-newtonsoft-how-to.md
• Product: dotnet
• GitHub Login: @tdykstra
• Microsoft Alias: tdykstra

[ahsonkhan]

I can certainly see that being helpful!