Bump NLog.Config from 4.6.7 to 4.6.8

Bumps [NLog.Config](https://github.com/NLog/NLog) from 4.6.7 to 4.6.8.
- [Release notes](https://github.com/NLog/NLog/releases)
- [Changelog](https://github.com/NLog/NLog/blob/v4.6.8/CHANGELOG.md)
- [Commits](https://github.com/NLog/NLog/compare/v4.6.7...v4.6.8)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

OhmGraphite/OhmGraphite.csproj

@@ -29,7 +29,7 @@
 
   <ItemGroup>
     <PackageReference Include="Costura.Fody" Version="3.3.2" />
-    <PackageReference Include="NLog.Config" Version="4.6.7" />
+    <PackageReference Include="NLog.Config" Version="4.6.8" />
     <PackageReference Include="Npgsql" Version="4.1.1" />
     <PackageReference Include="prometheus-net" Version="3.3.0" />
     <PackageReference Include="Resourcer.Fody" Version="1.7.3" />