Avoid coercing arrays to strings

Author: jjonescz

src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.Sdk.DefaultItems.targets

@@ -17,9 +17,9 @@ Copyright (c) .NET Foundation. All rights reserved.
          in case there is a solution/project in the current directory. -->
     <EnableDefaultItems Condition="'$(EnableDefaultItems)' == '' And
       '$(DisableDefaultItemsInProjectFolder)' == 'true' And
-      ('$([System.IO.Directory]::GetFiles($(MSBuildProjectDirectory), &quot;*.sln&quot;))' != '' Or
-      $([System.IO.Directory]::GetFiles($(MSBuildProjectDirectory), &quot;*.slnx&quot;)) != '' Or
-      $([System.IO.Directory]::GetFiles($(MSBuildProjectDirectory), &quot;*.*proj&quot;)) != '')">false</EnableDefaultItems>
+      ('$([System.IO.Directory]::GetFiles($(MSBuildProjectDirectory), &quot;*.sln&quot;).Length)' != '0' Or
+      '$([System.IO.Directory]::GetFiles($(MSBuildProjectDirectory), &quot;*.slnx&quot;).Length)' != '0' Or
+      '$([System.IO.Directory]::GetFiles($(MSBuildProjectDirectory), &quot;*.*proj&quot;).Length)' != '0')">false</EnableDefaultItems>
 
     <EnableDefaultItems Condition=" '$(EnableDefaultItems)' == '' ">true</EnableDefaultItems>
     <EnableDefaultCompileItems Condition=" '$(EnableDefaultCompileItems)' == '' ">true</EnableDefaultCompileItems>