[HOTFIX] Increase migration's database timeout (#8052)

We added a migration to add an index on the `PackageDependencies` table. This migration takes longer than 30 seconds to run on PROD and is timing out. This change increases the timeout to 30 minutes which we hope is enough to create the new index.

src/NuGetGallery/Migrations/MigrationsConfiguration.cs

@@ -1,6 +1,7 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using System.Data.Entity.Migrations;
 using System.Linq;
 using NuGet.Services.Entities;
@@ -12,6 +13,7 @@ public class MigrationsConfiguration : DbMigrationsConfiguration<EntitiesContext
         public MigrationsConfiguration()
         {
             AutomaticMigrationsEnabled = false;
+            CommandTimeout = (int)TimeSpan.FromMinutes(30).TotalSeconds;
         }
 
         protected override void Seed(EntitiesContext context)