Fix targets

Directory.Build.targets

@@ -1,5 +1,7 @@
 <Project>
   <PropertyGroup>
+    <RuntimeFrameworkVersion Condition=" '$(TargetFramework)' == 'netcoreapp2.0' ">$(MicrosoftNETCoreApp20PackageVersion)</RuntimeFrameworkVersion>
+    <RuntimeFrameworkVersion Condition=" '$(TargetFramework)' == 'netcoreapp2.1' ">$(MicrosoftNETCoreApp21PackageVersion)</RuntimeFrameworkVersion>
     <RuntimeFrameworkVersion Condition=" '$(TargetFramework)' == 'netcoreapp2.2' ">$(MicrosoftNETCoreApp22PackageVersion)</RuntimeFrameworkVersion>
     <NETStandardImplicitPackageVersion Condition=" '$(TargetFramework)' == 'netstandard2.0' ">$(NETStandardLibrary20PackageVersion)</NETStandardImplicitPackageVersion>
     <!-- aspnet/BuildTools#662 Don't police what version of NetCoreApp we use -->

build/dependencies.props

@@ -1,4 +1,4 @@
-<Project>
+<Project>
   <PropertyGroup>
     <MSBuildAllProjects>$(MSBuildAllProjects);$(MSBuildThisFileFullPath)</MSBuildAllProjects>
   </PropertyGroup>
@@ -8,6 +8,8 @@
     <MicrosoftAspNetCoreBenchmarkRunnerSourcesPackageVersion>2.2.0-preview1-34135</MicrosoftAspNetCoreBenchmarkRunnerSourcesPackageVersion>
     <MicrosoftAspNetCoreTestingPackageVersion>2.2.0-preview1-34135</MicrosoftAspNetCoreTestingPackageVersion>
     <MicrosoftExtensionsTypeNameHelperSourcesPackageVersion>2.2.0-preview1-34135</MicrosoftExtensionsTypeNameHelperSourcesPackageVersion>
+    <MicrosoftNETCoreApp20PackageVersion>2.0.0</MicrosoftNETCoreApp20PackageVersion>
+    <MicrosoftNETCoreApp21PackageVersion>2.2.0-preview1-26424-04</MicrosoftNETCoreApp21PackageVersion>
     <MicrosoftNETCoreApp22PackageVersion>2.2.0-preview1-26502-01</MicrosoftNETCoreApp22PackageVersion>
     <MicrosoftNETTestSdkPackageVersion>15.6.1</MicrosoftNETTestSdkPackageVersion>
     <MoqPackageVersion>4.7.49</MoqPackageVersion>