Revert default proxy logger source (#530)

* Revert default proxy logger source

* fix test

Author: yangpanMS

VERSION

@@ -1 +1 @@
-2.0.26
+2.0.27

src/VirtualClient/VirtualClient.Core.UnitTests/Proxy/ProxyLoggerTests.cs

@@ -48,7 +48,7 @@ public void ProxyLoggerUsesTheExpectedSourceWhenAnExplicitSourceIsProvided()
         }
 
         [Test]
-        public void ProxyLoggerHandlesCasesWhenAnExplicitSourceIsNotProvided()
+        public void ProxyLoggerDefaultsToVirtualClientWhenAnExplicitSourceIsNotProvided()
         {
             using (ProxyTelemetryChannel channel = new ProxyTelemetryChannel(this.mockProxyApiClient.Object))
             {
@@ -57,7 +57,7 @@ public void ProxyLoggerHandlesCasesWhenAnExplicitSourceIsNotProvided()
                 ProxyTelemetryMessage messageLogged = channel.FirstOrDefault();
 
                 Assert.IsNotNull(messageLogged);
-                Assert.IsNull(messageLogged.Source);
+                Assert.AreEqual("VirtualClient", messageLogged.Source);
             }
         }
     }

src/VirtualClient/VirtualClient.Core/Proxy/ProxyLogger.cs

@@ -37,7 +37,9 @@ public ProxyLogger(ProxyTelemetryChannel channel, string source = null)
             channel.ThrowIfNull(nameof(channel));
 
             this.Channel = channel;
-            this.Source = source;
+            this.Source = !string.IsNullOrWhiteSpace(source)
+                ? source
+                : "VirtualClient";
         }
 
         /// <summary>