fix examples

Author: alexwolfmsft

docs/azure/sdk/authentication/credential-chains.md

@@ -72,7 +72,7 @@ In its simplest form, you can use the parameterless version of `DefaultAzureCred
 
 To remove a credential from `DefaultAzureCredential`, use the corresponding `Exclude`-prefixed property in [DefaultAzureCredentialOptions](/dotnet/api/azure.identity.defaultazurecredentialoptions?view=azure-dotnet&preserve-view=true#properties). For example:
 
-:::code language="csharp" source="../snippets/authentication/credential-chains/Program.cs" id="snippet_DacExcludes" highlight="6-7":::
+:::code language="csharp" source="../snippets/authentication/credential-chains/Program.cs" id="snippet_DacExcludes" highlight="9-10":::
 
 In the preceding code sample, `EnvironmentCredential` and `WorkloadIdentityCredential` are removed from the credential chain. As a result, the first credential to be attempted is `ManagedIdentityCredential`. The modified chain looks like this:
 

docs/azure/sdk/snippets/authentication/credential-chains/Program.cs

@@ -31,6 +31,9 @@
 #region snippet_DacExcludes
 builder.Services.AddAzureClients(clientBuilder =>
 {
+    clientBuilder.AddBlobServiceClient(
+        new Uri("https://<account-name>.blob.core.windows.net"));
+
     clientBuilder.UseCredential(new DefaultAzureCredential(
         new DefaultAzureCredentialOptions
         {
@@ -44,6 +47,9 @@
 #region snippet_Ctc
 builder.Services.AddAzureClients(clientBuilder =>
 {
+    clientBuilder.AddBlobServiceClient(
+        new Uri("https://<account-name>.blob.core.windows.net"));
+
     clientBuilder.UseCredential(new ChainedTokenCredential(
         new ManagedIdentityCredential(clientId: userAssignedClientId),
         new VisualStudioCredential()));