Bump System.Linq.Dynamic.Core from 1.6.7 to 1.6.8

---
updated-dependencies:
- dependency-name: System.Linq.Dynamic.Core
  dependency-version: 1.6.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

Directory.Packages.props

@@ -7,7 +7,7 @@
     <PackageVersion Include="NUnit" Version="4.3.2" />
     <PackageVersion Include="NUnit3TestAdapter" Version="5.0.0" />
     <PackageVersion Include="StyleCop.Analyzers" Version="1.2.0-beta.556" />
-    <PackageVersion Include="System.Linq.Dynamic.Core" Version="1.6.7" />
+    <PackageVersion Include="System.Linq.Dynamic.Core" Version="1.6.8" />
     <PackageVersion Include="Tubular.ServerSide" Version="8.1.12" />
     <PackageVersion Include="Unosquare.Swan.Lite4" Version="4.0.0" />
   </ItemGroup>