Run code cleanup

Run code cleanup fromm Visual Studio 2019 16.1.

samples/Mvc.Client/Startup.cs

@@ -8,7 +8,6 @@
 using AspNet.Security.OpenId;
 using Microsoft.AspNetCore.Authentication.Cookies;
 using Microsoft.AspNetCore.Builder;
-using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.Extensions.DependencyInjection;
 

src/AspNet.Security.OpenId.Steam/SteamAuthenticationHandler.cs

@@ -128,6 +128,6 @@ protected override async Task<AuthenticationTicket> CreateTicketAsync(
             return context.Ticket;
         }
 
-        private new OpenIdAuthenticationEvents Events => (OpenIdAuthenticationEvents) base.Events;
+        private new OpenIdAuthenticationEvents Events => (OpenIdAuthenticationEvents)base.Events;
     }
 }

src/AspNet.Security.OpenId/OpenIdAuthenticationHandler.cs

@@ -323,7 +323,7 @@ protected override async Task HandleChallengeAsync(AuthenticationProperties prop
                     value: string.Join(",", Options.Attributes.Select(attribute => attribute.Key)));
             }
 
-            var address = QueryHelpers.AddQueryString(configuration.AuthenticationEndpoint, 
+            var address = QueryHelpers.AddQueryString(configuration.AuthenticationEndpoint,
                 message.GetParameters()
                     .ToDictionary(parameter => parameter.Key,
                                   parameter => parameter.Value));
@@ -434,6 +434,6 @@ private async Task<bool> VerifyAssertionAsync([NotNull] OpenIdAuthenticationMess
             return true;
         }
 
-        private new OpenIdAuthenticationEvents Events => (OpenIdAuthenticationEvents) base.Events;
+        private new OpenIdAuthenticationEvents Events => (OpenIdAuthenticationEvents)base.Events;
     }
 }