Update guidance and remove tables (#45123)

* Update credential guidance and remove tables

Co-authored-by: Scott Addie <[email protected]>

Author: alexwolfmsft

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+---
+ms.topic: include
+ms.date: 02/12/2025
+---
+
+## Authenticate to Azure services from your app
+
+The [Azure Identity library](/dotnet/api/azure.identity?view=azure-dotnet&preserve-view=true) provides various *credentials*&mdash;implementations of `TokenCredential` adapted to supporting different scenarios and Microsoft Entra authentication flows. The steps ahead demonstrate how to use <xref:Azure.Identity.ClientSecretCredential> when working with service principals locally and in production.

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+---
+ms.topic: include
+ms.date: 02/12/2025
+---
+
+[!INCLUDE [implement-service-principal-concepts](implement-service-principal-concepts.md)]
+
+### Implement the code
+
+Add the [Azure.Identity](/dotnet/api/azure.identity) package. In an ASP.NET Core project, also install the [Microsoft.Extensions.Azure](/dotnet/api/microsoft.extensions.azure) package:
+
+### [Command Line](#tab/command-line)
+
+In a terminal of your choice, navigate to the application project directory and run the following commands:
+
+```dotnetcli
+dotnet add package Azure.Identity
+dotnet add package Microsoft.Extensions.Azure
+```
+
+### [NuGet Package Manager](#tab/nuget-package)
+
+Right-click your project in the Visual Studio **Solution Explorer** window and select **Manage NuGet Packages**. Search for **Azure.Identity**, and install the matching package. Repeat this process for the **Microsoft.Extensions.Azure** package.
+
+:::image type="content" source="../media/nuget-azure-identity.png" alt-text="Install a package using the package manager.":::
+
+---
+
+Azure services are accessed using specialized client classes from the various Azure SDK client libraries. These classes and your own custom services should be registered for dependency injection so they can be used throughout your app. In `Program.cs`, complete the following steps to configure a client class for dependency injection and token-based authentication:
+
+1. Include the `Azure.Identity` and `Microsoft.Extensions.Azure` namespaces via `using` directives.
+1. Register the Azure service client using the corresponding `Add`-prefixed extension method.
+1. Configure `ClientSecretCredential` with the `tenantId`, `clientId`, and `clientSecret`.
+1. Pass the `ClientSecretCredential` instance to the `UseCredential` method.
+
+:::code language="csharp" source="../snippets/authentication/local-dev-service-principal/Program.cs" id="snippet_ClientSecretCredential_UseCredential":::
+
+An alternative to the `UseCredential` method is to provide the credential to the service client directly:
+
+:::code language="csharp" source="../snippets/authentication/local-dev-service-principal/Program.cs" id="snippet_ClientSecretCredential":::