Replace ** and Recursivedir for FastestCP test

When building on windows via commandline (both cmd and pwsh), it woudl
fail to find the Manialinks, and could also accidentally create a bunch
of recursive folders while trying to copy said files

tests/Modules/FastestCp.Tests/FastestCp.Tests.csproj

@@ -35,9 +35,9 @@
     </ItemGroup>
 
     <ItemGroup>
-        <ContentWithTargetPath Include="**\*.xml">
+        <ContentWithTargetPath Include="Manialinks\*.xml">
             <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-            <TargetPath>%(RecursiveDir)\%(Filename)%(Extension)</TargetPath>
+            <TargetPath>Manialinks\%(Filename)%(Extension)</TargetPath>
         </ContentWithTargetPath>
     </ItemGroup>