.Net: Updated dotnet README to align with SK 1.0.0-beta2 (#3212)

### Motivation and Context

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This PR contains changes to update `dotnet/README.md` file to be aligned
with recent SK version `1.0.0-beta2`.

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

dotnet/README.md

@@ -22,17 +22,18 @@ Copy and paste the following code into your project, with your Azure OpenAI key
 
 ```csharp
 using Microsoft.SemanticKernel;
+using Microsoft.SemanticKernel.Connectors.AI.OpenAI;
 
 var builder = new KernelBuilder();
 
 builder.WithAzureChatCompletionService(
-         "gpt-35-turbo",                  // Azure OpenAI Deployment Name
+         "gpt-35-turbo",                      // Azure OpenAI Deployment Name
          "https://contoso.openai.azure.com/", // Azure OpenAI Endpoint
          "...your Azure OpenAI Key...");      // Azure OpenAI Key
 
 // Alternative using OpenAI
 //builder.WithOpenAIChatCompletionService(
-//         "gpt-3.5-turbo",               // OpenAI Model name
+//         "gpt-3.5-turbo",                  // OpenAI Model name
 //         "...your OpenAI API Key...");     // OpenAI API Key
 
 var kernel = builder.Build();
@@ -41,7 +42,7 @@ var prompt = @"{{$input}}
 
 One line TLDR with the fewest words.";
 
-var summarize = kernel.CreateSemanticFunction(prompt, maxTokens: 100);
+var summarize = kernel.CreateSemanticFunction(prompt, requestSettings: new OpenAIRequestSettings { MaxTokens = 100 });
 
 string text1 = @"
 1st Law of Thermodynamics - Energy cannot be created or destroyed.
@@ -53,9 +54,9 @@ string text2 = @"
 2. The acceleration of an object depends on the mass of the object and the amount of force applied.
 3. Whenever one object exerts a force on another object, the second object exerts an equal and opposite on the first.";
 
-Console.WriteLine(await summarize.InvokeAsync(text1));
+Console.WriteLine(await kernel.RunAsync(text1, summarize));
 
-Console.WriteLine(await summarize.InvokeAsync(text2));
+Console.WriteLine(await kernel.RunAsync(text2, summarize));
 
 // Output:
 //   Energy conserved, entropy increases, zero entropy at 0K.
@@ -80,8 +81,8 @@ string summarizePrompt = @"{{$input}}
 
 Give me a TLDR with the fewest words.";
 
-var translator = kernel.CreateSemanticFunction(translationPrompt, maxTokens: 200);
-var summarize = kernel.CreateSemanticFunction(summarizePrompt, maxTokens: 100);
+var translator = kernel.CreateSemanticFunction(translationPrompt, requestSettings: new OpenAIRequestSettings { MaxTokens = 200 });
+var summarize = kernel.CreateSemanticFunction(summarizePrompt, requestSettings: new OpenAIRequestSettings { MaxTokens = 100 });
 
 string inputText = @"
 1st Law of Thermodynamics - Energy cannot be created or destroyed.