title: .Net Core 2.0 to 2.1: 'IMutableEntityType' does not contain a definition for 'Scaffolding'
body: <p>We have a .Net Core 2.0 API using a psql database.
  When updating to .Net Core 2.1, it stopped building and returned the following error:  </p>
  
  <pre><code>'IMutableEntityType' does not contain a definition for 'Scaffolding' and no extension method 'Scaffolding' accepting a first argument of type 'IMutableEntityType' could be found (are you missing a using directive or an assembly reference?)
  </code></pre>
  
  <p>This extension methods was not intended for external use, but we need it to change entities schema at runtime.</p>