🐛 Fix Apply Migrations button

During all the changes to how options are handled etc. we ended up where
app.UseDatabaseErrorPage() would no longer register the migrations
middleware that allows the "Apply Migrations" button to work.

Resolves aspnet/EntityFramework#4742

src/Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore/DatabaseErrorPageExtensions.cs

@@ -14,8 +14,7 @@ namespace Microsoft.AspNetCore.Builder
     {
         /// <summary>
         /// Captures synchronous and asynchronous database related exceptions from the pipeline that may be resolved using Entity Framework
-        /// migrations. When these exceptions occur an HTML response with details of possible actions to resolve the issue is generated. The
-        /// options for the middleware are set to display the maximum amount of information available.
+        /// migrations. When these exceptions occur an HTML response with details of possible actions to resolve the issue is generated.
         /// </summary>
         /// <param name="app">The <see cref="IApplicationBuilder"/> to register the middleware with.</param>
         /// <returns>The same <see cref="IApplicationBuilder"/> instance so that multiple calls can be chained.</returns>
@@ -26,7 +25,7 @@ namespace Microsoft.AspNetCore.Builder
                 throw new ArgumentNullException(nameof(app));
             }
 
-            return app.UseMiddleware<DatabaseErrorPageMiddleware>();
+            return app.UseDatabaseErrorPage(new DatabaseErrorPageOptions());
         }
 
         /// <summary>

src/Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore/MigrationsEndPointExtensions.cs

@@ -24,7 +24,7 @@ namespace Microsoft.AspNetCore.Builder
                 throw new ArgumentNullException(nameof(app));
             }
 
-            return app.UseMiddleware<MigrationsEndPointMiddleware>();
+            return app.UseMigrationsEndPoint(new MigrationsEndPointOptions());
         }
 
         /// <summary>