Import the new Microsoft.Common.Test.targets target for multi-tfm (#9598)

Co-authored-by: Marco Rossignoli <mrossignol@microsoft.com>

Author: github-actions[bot]

eng/Versions.props

@@ -2,7 +2,7 @@
 <!-- Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the MIT license. See License.txt in the project root for full license information. -->
 <Project>
   <PropertyGroup>
-    <VersionPrefix>17.9.0</VersionPrefix>
+    <VersionPrefix>17.9.1</VersionPrefix>
     <DotNetFinalVersionKind>release</DotNetFinalVersionKind>
     <PackageValidationBaselineVersion>17.8.3</PackageValidationBaselineVersion>
     <AssemblyVersion>15.1.0.0</AssemblyVersion>

src/Tasks/Microsoft.Common.CrossTargeting.targets

@@ -248,4 +248,9 @@ Copyright (C) Microsoft Corporation. All rights reserved.
 
   <Import Project="$(DirectoryBuildTargetsPath)" Condition="'$(ImportDirectoryBuildTargets)' == 'true' and exists('$(DirectoryBuildTargetsPath)')"/>
 
+  <PropertyGroup>
+    <UseMSBuildTestInfrastructure Condition="'$(UseMSBuildTestInfrastructure)' == ''">false</UseMSBuildTestInfrastructure>
+  </PropertyGroup>
+  <Import Project="$(MSBuildToolsPath)\Microsoft.Common.Test.targets" Condition="'$(UseMSBuildTestInfrastructure)' == 'true'"/>
+
 </Project>