Insight's `GroupBox` header is wrong colour or missing.

[Pressacco]

Caused by: #182

Behavior

After rolling back MaterialDesignInXaml NuGet package to v4.0.0, I noticed the following:

1. Open log file => Show Dashboard
   • GroupBox header is always the PrimaryColor (Red)
   • GroupBox header should be dark grey as per the XAML
     • InsightControl.xaml : materialDesign:ColorZoneAssist.Mode="SecondaryDark"
2. With the same instance of Weevil, open another log file (one that uses a plug-in's custom Dashboard)
   • GroupBox header is always missing (i.e. no color)
3. Restart Weevil
4. Open the log file from Step#2
   • GroupBox header is always PrimaryColor (i.e. red)
   • Previously: it was always missing (i.e. no color)
5. With the same instance of Weevil, open the log file from Step#1
   • GroupBox header is always missing (i.e. no color)
   • Previously: it was always red

[Pressacco]

Observations

• Problem appeared to be something cached in either bin or obj.
  • Visual Studio "Rebuild All" didn't help.
  • Had to manually delete the bin and obj directories.
• The built-in Dashboard and the custom `Dashboard (provided by a plug-in) now renders properly.