Refactor logging level handling and remove example usage

* Updated `CommandLineOptions` and `ConfigurationObject` to use `LoggingLevel` type instead of string for log levels.
* Modified `LoggerFactory` to set logging levels using the new `LoggingLevelMapping` methods.
* Removed the `example-usage.ts` file as it was no longer needed.
* Adjusted `Threshold` class to simplify logging level management.

test/config/Browserstack/SupportedBrowser.ts

@@ -7,4 +7,4 @@ type SupportedBrowser = {
     real_mobile: boolean;
 }
 
-export default SupportedBrowser
+export default SupportedBrowser;