Remove unused project reference

Author: Jack251970

Plugins/Flow.Launcher.Plugin.Sys/Flow.Launcher.Plugin.Sys.csproj

@@ -39,7 +39,6 @@
   <ItemGroup>
     <ProjectReference Include="..\..\Flow.Launcher.Infrastructure\Flow.Launcher.Infrastructure.csproj" />
     <ProjectReference Include="..\..\Flow.Launcher.Plugin\Flow.Launcher.Plugin.csproj" />
-    <ProjectReference Include="..\..\Flow.Launcher.Core\Flow.Launcher.Core.csproj" />
   </ItemGroup>
 
   <ItemGroup>