Remove FscTool{Path,Exe} overrides

Importing fsc.props, which overrides the values of FscToolPath and
FscToolExe, breaks my build on ubuntu with .NET Core 3.1. Removing the
import allows the build to work fine.

This commit should be reviewed later if we want to support .NET Core 2.0
(which is apparently what the overrides are for).

Author: canndrew

tests/DotNetLightning.Core.Tests/DotNetLightning.Core.Tests.fsproj

@@ -45,6 +45,5 @@
     <ProjectReference Condition="'$(BouncyCastle)'!='true'" Include="..\..\src\NSec\Experimental\NSec.Experimental.csproj" />
     <ProjectReference Include="..\..\src\ResultUtils\ResultUtils.fsproj" />
   </ItemGroup>
-  <Import Project="..\..\fsc.props" />
   <Import Project="..\..\netfx.props" />
 </Project>