highlight doesn't work on per page setting

[WebDucer]

Describe the bug

In documentation, the highlight option is described, as be able to set globally and per site.

If I set highlight = false in params.toml and highlight: true in page front matter, the code is not highlightet. As I can see, the CSS and JS files are included, but the <code> block has no class set to hljs, as this is set, when the global option ist set to true.

To Reproduce

Steps to reproduce the behavior:

1. Set highlight = false in params.toml
2. Set highlight: true for the single post
3. Write some code sample
4. Look at rendered result. It is not code highlighted

Expected behavior

The code should be highlighted, if the option is off globally, but on for the page.

Technical details:

• Link to your GitHub project:
• Wowchemy Version (from your go.mod): v0.0.0-20210123180413-7dbc1f73edfd
• Hugo Version (run hugo version): 0.8.0 extended
• Browser/OS: Chrome OS with Chrome Browser
• Wowchemy Template (e.g. Academic): Starter Blog

If applicable, add screenshots to help explain the issue.

Den Anfang machen wir mit einem sehr einfachen Model, das nur aus einer einzigen Tabelle (Objektklasse) besteht.

```csharp
public class WorkingTimeRange {
  public long Id { get; set; }
  public DateTime StartTime { get; set; }
  public DateTime EndTime { get; set; }
  public int PauseDuration { get; set; }
}

[gcushen]

There is a known issue related to Hugo's caching which affects Wowchemy v5.0.0 Beta 2: https://github.com/gohugoio/hugo/issues/7944

The workaround is to set highlight = true in params.toml until the page caching is resolved with a Hugo update.

Feel free to contribute to the Hugo issue.