CustomTasks.csproj

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

  <PropertyGroup>
    <TargetFramework Condition="'$(OS)' != 'Windows_NT'">netstandard2.0</TargetFramework>
    <TargetFramework Condition="'$(OS)' == 'Windows_NT'">net45</TargetFramework>
    <AssemblyName>CustomTasks</AssemblyName>
    <RootNamespace>CustomTasks</RootNamespace>
    <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
    <OutputType>Library</OutputType>
    <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
    <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
  </ItemGroup>

  <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
    <PackageReference Include="Microsoft.Build.Framework" Version="16.11.0" />
    <PackageReference Include="Microsoft.Build.Utilities.Core" Version="16.11.0" />
  </ItemGroup>

  <ItemGroup Condition="'$(TargetFramework)' == 'net45'">
    <Reference Include="Microsoft.Build.Framework" />
    <Reference Include="Microsoft.Build.Utilities.v4.0" />
  </ItemGroup>

  <ItemGroup>
    <None Include="Endpoint\endpoints-override.json">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
  </ItemGroup>
</Project>