Revert 2 recent test commits

* Revert "FileConventions.Test: make versions consistent":
This reverts commit db12f32.

* Revert "FileConventions.Test: inconsistent nuget version":
This reverts commit c140edb.

Now that we see they passed in the fork branch of the PR, we can
revert them.

src/FileConventions/FileConventions.fsproj

@@ -13,7 +13,6 @@
   <ItemGroup>
     <PackageReference Include="Mono.Posix" Version="7.1.0-final.1.21458.1" />
     <PackageReference Include="Mono.Unix" Version="7.1.0-final.1.21458.1" />
-    <PackageReference Include="Fsdk" Version="0.6.0--date20230214-0422.git-1ea6f62" />
   </ItemGroup>
 
 </Project>