Update FShap project: LangVersion is set according to target framework

Author: alex-kulakov

Orm/Xtensive.Orm.Tests.FSharp/Xtensive.Orm.Tests.FSharp.fsproj

@@ -6,12 +6,20 @@
     <Configurations>Debug;Release;Debug-NET6;Release-NET6;Debug-NET7;Release-NET7;Debug-NET8;Release-NET8</Configurations>
   </PropertyGroup>
   <PropertyGroup>
-    <LangVersion>4.7</LangVersion>
     <SignAssembly>true</SignAssembly>
     <AssemblyOriginatorKeyFile>$(OrmKeyFile)</AssemblyOriginatorKeyFile>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <WarningLevel>2</WarningLevel>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(TargetFramework)'=='net6.0'">
+    <LangVersion>6.0</LangVersion>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(TargetFramework)'=='net7.0'">
+    <LangVersion>7.0</LangVersion>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(TargetFramework)'=='net8.0'">
+    <LangVersion>8.0</LangVersion>
+  </PropertyGroup>
   <Import Project="$(SolutionDir)MSBuild\DataObjects.Net.InternalBuild.targets" />
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
@@ -28,7 +36,13 @@
     <Compile Include="Test.fs" />
     <None Include="App.config" />
   </ItemGroup>
-  <ItemGroup>
-    <PackageReference Update="FSharp.Core" Version="4.7.0" />
+  <ItemGroup Condition="'$(TargetFramework)'=='net6.0'">
+    <PackageReference Update="FSharp.Core" Version="6.0.7" />
+  </ItemGroup>
+  <ItemGroup Condition="'$(TargetFramework)'=='net7.0'">
+    <PackageReference Update="FSharp.Core" Version="7.0.403" />
+  </ItemGroup>
+  <ItemGroup Condition="'$(TargetFramework)'=='net8.0'">
+    <PackageReference Update="FSharp.Core" Version="8.0.403" />
   </ItemGroup>
 </Project>