Add Sdk.BundledVersions.props

Needed to unblock dotnet/arcade#16413 to workaround dotnet/msbuild#12895 but in general offers a way to import BundledVersions.props information from projects that don't import the Microsoft.NET.Sdk.

Author: ViktorHofer

src/Tasks/Microsoft.NET.Build.Tasks/sdk/Sdk.BundledVersions.props

@@ -0,0 +1,21 @@
+<!--
+***********************************************************************************************
+Sdk.BundledVersions.props
+
+WARNING:  DO NOT MODIFY this file unless you are knowledgeable about MSBuild and have
+          created a backup copy.  Incorrect changes to this file will make it
+          impossible to load or build your projects from the command-line or the IDE.
+
+Copyright (c) .NET Foundation. All rights reserved.
+***********************************************************************************************
+-->
+<Project ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+
+  <!-- Imported by components that need the BundledVerisons.props information but don't import the entire Microsoft.NET.Sdk -->
+
+  <PropertyGroup Condition="'$(NETCoreSdkBundledVersionsProps)' == ''">
+    <NETCoreSdkBundledVersionsProps>$(MSBuildThisFileDirectory)..\..\..\Microsoft.NETCoreSdk.BundledVersions.props</NETCoreSdkBundledVersionsProps>
+  </PropertyGroup>
+  <Import Project="$(NETCoreSdkBundledVersionsProps)" Condition="Exists('$(NETCoreSdkBundledVersionsProps)')" /> 
+
+</Project>