UploadWizardExceptionFlowEvent is used to track JS exceptions that occur in UploadWizard.
We shouldn't be using EventLogging for error logging, and I don't think we're currently doing anything with that data anyway.

(UploadWizardErrorFlowEvent is probably fine - that is used to log errors based on user input (e.g. invalid/duplicate file names etc.) that can be used to inform us when the interface might not be clear enough. Though we might want to look into its usage as well after T191081)