feat: .NET appsettings files in repos (#88)

Co-authored-by: Karl-Einar Bergstrøm <karl-einarb@outlook.com>

docs/config.md

@@ -76,6 +76,7 @@ theme:
   repoColor: ["#c099ff"]
   springColor: ["#c3e88d"]               # Spring Boot config files
   composeColor: ["#82aaff"]              # Docker Compose files
+  dotnetColor: ["#c099ff"]               # .NET appsettings files
 ```
 
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