Issue Description

Problem encountered in MudBlazor/MudBlazor#5801

  <Target Name="IncludeGeneratedStaticFiles" DependsOnTargets="WebCompiler" BeforeTargets="BeforeBuild">
    <ItemGroup>
      <!--Include without duplication-->
      <_NewCompiledDocsCssFiles Include="wwwroot/MudBlazorDocs.min.css" Exclude="@(Content)" />
      <Content Include="@(_NewCompiledDocsCssFiles)" />
    </ItemGroup>
  </Target>

It seems Include="wwwroot/MudBlazorDocs.min.css" pattern with Exclude=@(Content) fails to remove duplicates on windows. I need to use \ (backslash) for path separator in order for it to work on Windows and Linux/mac

In all our project files we normally use / (forward slash) for path separators and the problem didn't show up on mac or build servers (Linux).

However windows users local builds started to fail.

In the following example wwwroot/MudBlazorDocs.min.css as the Include pattern fails on Windows platform with duplicate content files.

If I change it to wwwroot\MudBlazorDocs.min.css the Content is correct and the build succeeds with no duplicate Content files

Steps to Reproduce

Repo

Build MudBlazor/MudBlazor#5801 on Windows (fails)
Build MudBlazor/MudBlazor#5801 on OS with / path separator (succeeds)

Alternatively use HEAD of dev and change the following lines to a forward slash the build will fail on windows but succeed on Linux/mac

https://github.com/MudBlazor/MudBlazor/blob/2f65df6b8d39ddd7109bce58648ad60be606f177/src/MudBlazor/MudBlazor.csproj#L91
https://github.com/MudBlazor/MudBlazor/blob/2f65df6b8d39ddd7109bce58648ad60be606f177/src/MudBlazor/MudBlazor.csproj#L92
https://github.com/MudBlazor/MudBlazor/blob/2f65df6b8d39ddd7109bce58648ad60be606f177/src/MudBlazor.Docs/MudBlazor.Docs.csproj#L113

Expected Behavior

To be able to use / everywhere as the path separator for Xplat builds

Actual Behavior

The Include Exclude pair fails and duplicate files are passed to Microsoft.NET.Sdk.Razor.StaticWebAssets
C:\Program Files\dotnet\sdk\7.0.100\Sdks\Microsoft.NET.Sdk.Razor\targets\Microsoft.NET.Sdk.Razor.StaticWebAssets.target s(419,5): error : Two assets found targeting the same path with incompatible asset kinds:

Analysis

Something to do with path separators and string comparisons only when using forward slash as path separator
Seems similar to #724
However that looks like it had a fix

Versions & Configurations

dotnet msbuild --version
MSBuild version 17.4.0+18d5aef85 for .NET
17.4.0.51802

• If applicable, include the version of the tool that invokes MSBuild (Visual Studio, dotnet CLI, etc):

dotnet --version
7.0.100