Bug and unclear

Bug: In the "Refactor the code" section, the 1st C# code is missing the client parameter that is needed.

The use of Write versus Writeline here detracts on understanding what is going on when running the example.
Step 2 of "Making HTTP Requests" could use a lot more explanation. The Accept header is doing what? Limiting the results to only application/json returns. Why the extra stuff (vnd.github.v3+)?
The User Agent string can be anything. Feel free to change this. What is Github doing with it, etc.

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#### Document Details

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* ID: 3bfcc1a8-ddda-810c-17b0-56a506045d67
* Version Independent ID: 5415878b-e60b-5433-7b4b-efc8259908f0
* Content: [Tutorial: Make HTTP requests in a .NET console app using C#](https://learn.microsoft.com/en-us/dotnet/csharp/tutorials/console-webapiclient)
* Content Source: [docs/csharp/tutorials/console-webapiclient.md](https://github.com/dotnet/docs/blob/main/docs/csharp/tutorials/console-webapiclient.md)
* Product: **dotnet-csharp**
* Technology: **csharp-fundamentals**
* GitHub Login: @BillWagner
* Microsoft Alias: **wiwagn**