.Net: Small fixes for examples (#4354)

### Motivation and Context

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Fixed initialization of `AzureOpenAIChatCompletionService` in examples.

### Contribution Checklist

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- [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)
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raises no violations
- [x] All unit tests pass, and I have added new tests where possible
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dotnet/samples/KernelSyntaxExamples/Example17_ChatGPT.cs

@@ -57,10 +57,10 @@ private static async Task AzureOpenAIChatSampleAsync()
         Console.WriteLine("======== Azure Open AI - ChatGPT ========");
 
         AzureOpenAIChatCompletionService chatCompletionService = new(
-            TestConfiguration.AzureOpenAI.ChatDeploymentName,
-            TestConfiguration.AzureOpenAI.ChatModelId,
-            TestConfiguration.AzureOpenAI.Endpoint,
-            TestConfiguration.AzureOpenAI.ApiKey);
+            deploymentName: TestConfiguration.AzureOpenAI.ChatDeploymentName,
+            endpoint: TestConfiguration.AzureOpenAI.Endpoint,
+            apiKey: TestConfiguration.AzureOpenAI.ApiKey,
+            modelId: TestConfiguration.AzureOpenAI.ChatModelId);
 
         await StartChatAsync(chatCompletionService);
     }

dotnet/samples/KernelSyntaxExamples/Example33_StreamingChat.cs

@@ -29,10 +29,10 @@ private static async Task AzureOpenAIChatStreamSampleAsync()
         Console.WriteLine("======== Azure Open AI - ChatGPT Streaming ========");
 
         AzureOpenAIChatCompletionService chatCompletionService = new(
-           TestConfiguration.AzureOpenAI.ChatDeploymentName,
-           TestConfiguration.AzureOpenAI.ChatModelId,
-           TestConfiguration.AzureOpenAI.Endpoint,
-           TestConfiguration.AzureOpenAI.ApiKey);
+            deploymentName: TestConfiguration.AzureOpenAI.ChatDeploymentName,
+            endpoint: TestConfiguration.AzureOpenAI.Endpoint,
+            apiKey: TestConfiguration.AzureOpenAI.ApiKey,
+            modelId: TestConfiguration.AzureOpenAI.ChatModelId);
 
         await StartStreamingChatAsync(chatCompletionService);
     }

dotnet/samples/KernelSyntaxExamples/Example44_MultiChatCompletion.cs

@@ -20,10 +20,10 @@ private static async Task AzureOpenAIMultiChatCompletionAsync()
         Console.WriteLine("======== Azure OpenAI - Multiple Chat Completion ========");
 
         AzureOpenAIChatCompletionService chatCompletionService = new(
-            TestConfiguration.AzureOpenAI.ChatDeploymentName,
-            TestConfiguration.AzureOpenAI.ChatModelId,
-            TestConfiguration.AzureOpenAI.Endpoint,
-            TestConfiguration.AzureOpenAI.ApiKey);
+            deploymentName: TestConfiguration.AzureOpenAI.ChatDeploymentName,
+            endpoint: TestConfiguration.AzureOpenAI.Endpoint,
+            apiKey: TestConfiguration.AzureOpenAI.ApiKey,
+            modelId: TestConfiguration.AzureOpenAI.ChatModelId);
 
         await RunChatAsync(chatCompletionService);
     }