build(deps): bump Markdig from 0.33.0 to 0.34.0 (dotnet#9528)

Bumps [Markdig](https://github.com/xoofx/markdig) from 0.33.0 to 0.34.0.
- [Release notes](https://github.com/xoofx/markdig/releases)
- [Changelog](https://github.com/xoofx/markdig/blob/master/changelog.md)
- [Commits](xoofx/markdig@0.33.0...0.34.0)

---
updated-dependencies:
- dependency-name: Markdig
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Directory.Packages.props

@@ -9,7 +9,7 @@
     <PackageVersion Include="IgnoresAccessChecksToGenerator" Version="0.7.0" />
     <PackageVersion Include="Jint" Version="3.0.0-beta-2057" />
     <PackageVersion Include="JsonSchema.Net" Version="5.4.2" />
-    <PackageVersion Include="Markdig" Version="0.33.0" />
+    <PackageVersion Include="Markdig" Version="0.34.0" />
     <!-- "17.3.2" is the latest compatible version for .NET 6 -->
     <PackageVersion Include="Microsoft.Build" Version="[17.3.2]" Condition="'$(TargetFramework)' == 'net6.0'" />
     <PackageVersion Include="Microsoft.Build" Version="[17.7.2]" Condition="'$(TargetFramework)' == 'net7.0'" />