title: Warning NETSDK1071 A PackageReference to 'Microsoft.AspNetCore.App' specified a Version of `2.1.6`
body: <p>I have the following warning </p>
  
  <pre><code> Severity   Code    Description Project File    Line    Suppression State
  Warning NETSDK1071  A PackageReference to 'Microsoft.AspNetCore.App' specified a Version of `2.1.6`. Specifying the version of this package is not recommended. For more information, see https://aka.ms/sdkimplicitrefs    MyApi   C:\Program Files\dotnet\sdk\2.2.102\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.Sdk.DefaultItems.targets   153 
  </code></pre>
  
  <p>I tried removing the reference by editing the project file and then adding the nuget package, however when I did this a lot of references no longer worked correctly.</p>
  
  <p>I note the error is mentioning sdk\2.2 which I did install recently on my computer but there is no reference to it in the project file.</p>
  
  <p>I am using VS2017 15.9.5</p>