Set connection limit for google endpoint (#628)

src/Diagnostics.RuntimeHost/Services/HealthCheckService/HealthCheckService.cs

@@ -158,11 +158,13 @@ namespace Diagnostics.RuntimeHost.Services
 
         private void InitializeHttpClient()
         {
-            _httpClient = new HttpClient
+            var handler = new HttpClientHandler
             {
-                MaxResponseContentBufferSize = Int32.MaxValue,
+                MaxConnectionsPerServer = 10 // Set only max of 10 concurrent connections to google endpoint.
-                Timeout = TimeSpan.FromSeconds(3)
             };
+            _httpClient = new HttpClient(handler);
+            _httpClient.MaxResponseContentBufferSize = Int32.MaxValue;
+            _httpClient.Timeout = TimeSpan.FromSeconds(3);
         }
     }
 }