Remove U2D marker dependency on ProjectGuid property (#9504)

* Version 17.10 (#9499)

* Remove U2D marker dependency on ProjectGuid property

* Revert "Version 17.10"

---------

Co-authored-by: AR-May <67507805+AR-May@users.noreply.github.com>

src/Tasks/Microsoft.Common.CurrentVersion.targets

@@ -388,9 +388,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
 
   <PropertyGroup Condition="'$(MSBuildCopyMarkerName)' == ''">
     <MSBuildCopyMarkerName>$(MSBuildProjectFile)</MSBuildCopyMarkerName>
-    <!-- For a long MSBuildProjectFile let's shorten this to 17 chars - using the first 8 chars of the filename and either the ProjectGuid if it exists -->
-    <MSBuildCopyMarkerName Condition="'$(MSBuildCopyMarkerName.Length)' &gt; '17' and '$(ProjectGuid)' != ''">$(MSBuildProjectFile.Substring(0,8)).$(ProjectGuid.Substring(1,8))</MSBuildCopyMarkerName>
-    <!-- or a filename hash if the guid is not present (in such case the filename was not shortened and is still over 17 chars long). -->
+    <!-- For a long MSBuildProjectFile let's shorten this to 17 chars - using the first 8 chars of the filename and a filename hash. -->
     <MSBuildCopyMarkerName Condition="'$(MSBuildCopyMarkerName.Length)' &gt; '17'">$(MSBuildProjectFile.Substring(0,8)).$([MSBuild]::StableStringHash($(MSBuildProjectFile)).ToString("X8"))</MSBuildCopyMarkerName>
     <MSBuildCopyMarkerName>$(MSBuildCopyMarkerName).Up2Date</MSBuildCopyMarkerName>
   </PropertyGroup>