Aspnetcore.docs: Adding Xml support

[kingmotley]

Currently, the alternative way of adding XML support as suggested https://docs.microsoft.com/en-us/aspnet/core/web-api/advanced/formatting?view=aspnetcore-2.2#adding-xml-format-support, will cause the ProblemDetails and ValidationProblemDetails to be serialized incorrectly because they are only wrapped correctly when you call .AddXmlSerializerFormatters(); as I found out when I reported the issue as a bug https://github.com/aspnet/AspNetCore/issues/7715

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Document Details

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• ID: 6ebcd752-af71-c483-eebb-0745bd04fb30
• Version Independent ID: 1f678d5d-230b-0ad0-c925-15b13081f553
• Content: Format response data in ASP.NET Core Web API
• Content Source: aspnetcore/web-api/advanced/formatting.md
• Product: aspnet-core
• GitHub Login: @ardalis
• Microsoft Alias: riande

[Rick-Anderson]

@kingmotley thanks for reporting this. Would you be able to provide the first draft of updating this doc?

@pranavkm do you agree we should update this doc with the instructions you provided in https://github.com/aspnet/AspNetCore/issues/7715?

[pranavkm]

Yeah. Removing the alternatives would be the way to go.

[sumon19]

nice

[Rick-Anderson]