Updates to Copilot highlights per revised guidance

[anandmeg]

Updates per revised guidance based on dotnet team's feedback.

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Internal previews

📄 File	🔗 Preview link
docs/csharp/how-to/concatenate-multiple-strings.md	How to concatenate multiple strings (C# Guide)
docs/csharp/how-to/parse-strings-using-split.md	"Divide strings using String.Split"
docs/csharp/programming-guide/classes-and-structs/how-to-initialize-a-dictionary-with-a-collection-initializer.md	How to initialize a dictionary with a collection initializer (C# Programming Guide)
docs/csharp/programming-guide/types/how-to-convert-a-string-to-a-number.md	docs/csharp/programming-guide/types/how-to-convert-a-string-to-a-number
docs/standard/serialization/system-text-json/customize-properties.md	How to customize property names and values with System.Text.Json
docs/standard/serialization/system-text-json/deserialization.md	How to read JSON as .NET objects (deserialize)
docs/standard/serialization/system-text-json/how-to.md	"How to serialize JSON in C#"
docs/standard/serialization/system-text-json/migrate-from-newtonsoft.md	Migrate from Newtonsoft.Json to System.Text.Json

[gewarren]

Please batch the suggestions so it doesn't kick off multiple builds.

[anandmeg]

Please batch the suggestions so it doesn't kick off multiple builds.

Please batch the suggestions so it doesn't kick off multiple builds.
Add suggestions to batch isn't available to me.

[adegeo]

Please batch the suggestions so it doesn't kick off multiple builds.

Please batch the suggestions so it doesn't kick off multiple builds.
Add suggestions to batch isn't available to me.

That's odd, there's something wrong there. Batching has been around for years. Maybe you can share a bigger screenshot.

[anandmeg]

Please batch the suggestions so it doesn't kick off multiple builds.

Please batch the suggestions so it doesn't kick off multiple builds.
Add suggestions to batch isn't available to me.

That's odd, there's something wrong there. Batching has been around for years. Maybe you can share a bigger screenshot.

yes I'm surprised too. I've used it in the past on other PRs.

[BillWagner]

This LGTM. I'll