Add ResponseExtensions tests

sdk/resourcemanager/Azure.ResourceManager.Core/src/Extensions/ResponseExtensions.cs

@@ -14,7 +14,7 @@ public static class ResponseExtensions
         public static string GetCorrelationId(this Response response)
         {
             string correlationId = null;
-            response.Headers.TryGetValue("x-ms-correlation-id", out correlationId);
+            response.Headers.TryGetValue("x-ms-correlation-request-id", out correlationId);
             return correlationId;
         }
     }

sdk/resourcemanager/Azure.ResourceManager.Core/tests/Scenario/ResponseExtensionsTests.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Net.Http;
+using System.Threading.Tasks;
+using Azure.Core;
+using Azure.Core.TestFramework;
+using NUnit.Framework;
+
+namespace Azure.ResourceManager.Core.Tests
+{
+    public class ResponseExtensionsTests : ResourceManagerTestBase
+    {
+        public ResponseExtensionsTests(bool isAsync)
+            : base(isAsync)//, RecordedTestMode.Record)
+        {
+        }
+
+        [TestCase]
+        [RecordedTest]
+        public async Task GetCorrelationId()
+        {
+            var correlationId = "0a98bb8b-ec3e-4f68-a8c1-a7705554a980";
+            var pipeline = Client.DefaultSubscription.Pipeline;
+            var endpoint = new Uri("https://management.azure.com");
+            var message = pipeline.CreateMessage();
+            var request = message.Request;
+            request.Method = RequestMethod.Get;
+            var uri = new RawRequestUriBuilder();
+            uri.Reset(endpoint);
+            uri.AppendPath("/subscriptions/", false);
+            uri.AppendPath(TestEnvironment.SubscriptionId, true);
+            uri.AppendQuery("api-version", "2019-11-01", true);
+            request.Uri = uri;
+            request.Headers.Add("Accept", "application/json");
+            request.Headers.Add("x-ms-correlation-request-id", correlationId);
+
+            await pipeline.SendAsync(message, default).ConfigureAwait(false);
+            var response = message.Response;
+            Assert.AreEqual(correlationId, ResponseExtensions.GetCorrelationId(response));
+        }
+    }
+}