update C# samples with throwOnAnyError enabled (OpenAPITools#23685)

Author: wing328

bin/configs/csharp-restsharp-net4.7-multipleFrameworks.yaml

@@ -8,3 +8,4 @@ additionalProperties:
   targetFramework: netstandard2.1;net47
   useCompareNetObjects: "true"
   equatable: true
+  throwOnAnyError: true

samples/client/petstore/csharp/restsharp/net4.7/MultipleFrameworks/src/Org.OpenAPITools/Client/ApiClient.cs

@@ -468,7 +468,8 @@ private async Task<ApiResponse<T>> ExecClientAsync<T>(Func<RestClient, Task<Rest
                 Proxy = configuration.Proxy,
                 UserAgent = configuration.UserAgent,
                 UseDefaultCredentials = configuration.UseDefaultCredentials,
-                RemoteCertificateValidationCallback = configuration.RemoteCertificateValidationCallback
+                RemoteCertificateValidationCallback = configuration.RemoteCertificateValidationCallback,
+                ThrowOnAnyError = true
             };
             setOptions(clientOptions);
 
@@ -565,10 +566,7 @@ private async Task<RestResponse<T>> DeserializeRestResponseFromPolicyAsync<T>(Re
             }
             else
             {
-                return new RestResponse<T>(request)
-                {
-                    ErrorException = policyResult.FinalException
-                };
+                throw policyResult.FinalException ?? new InvalidOperationException("The retry policy failed without an exception.");
             }
         }