.Net: Update README with feedback from Bug Bash (#9249)

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dotnet/samples/GettingStarted/README.md

@@ -8,7 +8,7 @@ The examples can be run as integration tests but their code can also be copied t
 
 Most of the examples will require secrets and credentials, to access OpenAI, Azure OpenAI,
 Bing and other resources. We suggest using .NET
-[Secret Manager](https://learn.microsoft.com/en-us/aspnet/core/security/app-secrets)
+[Secret Manager](https://learn.microsoft.com/aspnet/core/security/app-secrets)
 to avoid the risk of leaking secrets into the repository, branches and pull requests.
 You can also use environment variables if you prefer.
 

dotnet/samples/GettingStartedWithTextSearch/README.md

@@ -8,10 +8,13 @@ The examples can be run as integration tests but their code can also be copied t
 
 Most of the examples will require secrets and credentials, to access OpenAI, Azure OpenAI,
 Bing and other resources. We suggest using .NET
-[Secret Manager](https://learn.microsoft.com/en-us/aspnet/core/security/app-secrets)
+[Secret Manager](https://learn.microsoft.com/aspnet/core/security/app-secrets)
 to avoid the risk of leaking secrets into the repository, branches and pull requests.
 You can also use environment variables if you prefer.
 
+**NOTE**
+The `Step2_Search_For_RAG.RagWithBingTextSearchUsingFullPagesAsync` sample requires a large context window so we recommend using `gpt-4o` or `gpt-4o-mini` models.
+
 To set your secrets with Secret Manager:
 
 ```
@@ -23,6 +26,10 @@ dotnet user-secrets set "OpenAI:EmbeddingModelId" "..."
 dotnet user-secrets set "OpenAI:ChatModelId" "..."
 dotnet user-secrets set "OpenAI:ApiKey" "..."
 
+dotnet user-secrets set "Bing:ApiKey" "..."
+
+dotnet user-secrets set "Google:SearchEngineId" "..."
+dotnet user-secrets set "Google:ApiKey" "..."
 ```
 
 To set your secrets with environment variables, use these names:
@@ -31,4 +38,9 @@ To set your secrets with environment variables, use these names:
 OpenAI__EmbeddingModelId
 OpenAI__ChatModelId
 OpenAI__ApiKey
+
+Bing__ApiKey
+
+Google__SearchEngineId
+Google__ApiKey
 ```

dotnet/samples/GettingStartedWithTextSearch/Step2_Search_For_RAG.cs

@@ -266,7 +266,7 @@ public async Task RagWithBingTextSearchUsingFullPagesAsync()
         // Create a kernel with OpenAI chat completion
         IKernelBuilder kernelBuilder = Kernel.CreateBuilder();
         kernelBuilder.AddOpenAIChatCompletion(
-                modelId: TestConfiguration.OpenAI.ChatModelId,
+                modelId: TestConfiguration.OpenAI.ChatModelId, // Requires a large context window e.g. gpt-4o or gpt-4o-mini 
                 apiKey: TestConfiguration.OpenAI.ApiKey);
         Kernel kernel = kernelBuilder.Build();
 

dotnet/src/SemanticKernel.Core/Data/TextSearch/VectorStoreTextSearch.cs

@@ -108,8 +108,6 @@ public VectorStoreTextSearch(
         VectorStoreTextSearchOptions? options = null)
     {
         Verify.NotNull(vectorizableTextSearch);
-        Verify.NotNull(stringMapper);
-        Verify.NotNull(resultMapper);
 
         this._vectorizableTextSearch = vectorizableTextSearch;
         this._propertyReader = new Lazy<TextSearchResultPropertyReader>(() => new TextSearchResultPropertyReader(typeof(TRecord)));