Update external tool when you add data sources to Ground Truth Labeler app
the option to update the external tool when a new data source is loaded into the Ground
Truth Labeler app. The app calls this method using the
connectorObj object. You can optionally use this method to react to a
new data source being connected to the app.
A new data source can be a video, image sequence, or custom reader. You can load a new data source while loading a new session.
The client class can optionally implement this method.