title: Package restore failed Issue for Scaffolding items
body: <p>I have issues creating a Controller with Scaffolding items.
  I'm working with Visual Studio 2019 - ASP.NET Core Web Application (with MVC) - ASP.NET Core 3.1</p>
  <p>I did the following steps:</p>
  <ol>
  <li>I installed from Nuget Packages Manager:</li>
  </ol>
  <ul>
  <li>Microsoft.EntityFrameworkCore (3.1.3)</li>
  <li>Microsoft.EntityFrameworkCore.SQLServer (3.1.3)</li>
  <li>Microsoft.EntityFrameworkCore.Tools (3.1.3)</li>
  </ul>
  <ol start="2">
  <li>I made a Model class</li>
  <li>I made a DB context class</li>
  <li>I added in the ConfigureServices method of Startup class the connection with the DB context and String connection</li>
  <li>In appsettings.json I added the String connection to SQLSERVER</li>
  <li>right-click on Controllers folder, Add &gt; Controller. Then select ‘MVC Controller with views, using Entity Framework’, selected Model and DB Context but when it's creating the Controller and View the VS showed me an error &quot;Package restore failed. Rolling back package changes for &quot;Name of Project&quot; &quot;</li>
  </ol>
  <p>I read other questions related to this, I delete the cache from the Nuget Packages, Rebuild project, change the version of the packages, etc, but the issue still happening.</p>