Bump System.Data.SqlClient in /snippets/fsharp/System/Convert/IsDBNull (#9553)

Bumps [System.Data.SqlClient](https://github.com/dotnet/corefx) from 4.8.3 to 4.8.6.
- [Release notes](https://github.com/dotnet/corefx/releases)
- [Commits](https://github.com/dotnet/corefx/commits)

---
updated-dependencies:
- dependency-name: System.Data.SqlClient
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

snippets/fsharp/System/Convert/IsDBNull/fs.fsproj

@@ -8,6 +8,6 @@
     <Compile Include="Form1.fs" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="System.Data.SqlClient" Version="4.8.3" />
+    <PackageReference Include="System.Data.SqlClient" Version="4.8.6" />
   </ItemGroup>
 </Project>