I am trying to resolve nugget packages with dotnet restore, but am getting the following error:

Unable to resolve 'Microsoft.NETCore.App (>= 2.1.0)' for '.NETCoreApp,Version=v2.1'

Here's my .csproj file

<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>netcoreapp2.1</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Autofac" Version="4.5.0" />
    <PackageReference Include="Autofac.Extensions.DependencyInjection" Version="4.1.0" />
    <PackageReference Include="Autofac.Extras.Moq" Version="4.2.0" />
    <PackageReference Include="BCrypt.Net-Core" Version="1.4.0" />
    <PackageReference Include="Easy.MessageHub" Version="3.2.1" />
    <PackageReference Include="hangfire" Version="1.6.17" />
    <PackageReference Include="Hangfire.MemoryStorage" Version="1.5.2" />
    <PackageReference Include="Microsoft.AspNetCore.App" Version="2.1.0-rc1-final" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.1.0-rc1-final" />
    <PackageReference Include="Microsoft.Extensions.Configuration" Version="2.1.0-rc1-final" />
    <PackageReference Include="MongoDB.Driver" Version="2.4.4" />
    <PackageReference Include="Swashbuckle.AspNetCore" Version="1.1.0" />
    <PackageReference Include="System.Runtime.Extensions" Version="4.3.0" />
  </ItemGroup>

  <Target Name="ApplyXdtConfigTransform" BeforeTargets="_TransformWebConfig">
    <PropertyGroup>
      <_SourceWebConfig>$(MSBuildThisFileDirectory)Web.config</_SourceWebConfig>
      <_XdtTransform>$(MSBuildThisFileDirectory)Web.$(Configuration).config</_XdtTransform>
      <_TargetWebConfig>$(PublishDir)Web.config</_TargetWebConfig>
    </PropertyGroup>
    <Exec Command="dotnet transform-xdt --xml &quot;$(_SourceWebConfig)&quot; --transform &quot;$(_XdtTransform)&quot; --output &quot;$(_TargetWebConfig)&quot;" Condition="Exists('$(_XdtTransform)')" />
  </Target>
</Project>

I have installed dotnet-sdk-2.1.300-rc1-008673-win-x64 and I am using Visual Studio 2017 v15.2