You can’t.
The message is displayed by macOS every time you launch VMware Fusion because of the way Fusion is starting its background services using an older method that Apple has deprecated. . Fusion adds the scripts to start and stop its background services to macOS every time Fusion starts, and removes those scripts when you quit Fusion. The adding of the scripts triggers the notification by macOS. There’s no setting that turns this notification off.
The message is an annoyance, but is not an indication of a problem.
I remember seeing a “workaround” for this a couple of years ago that involved copying some of those service management scripts. I don’t recommend their use.
This won’t get fixed until Fusion switches to a newer (and more secure) method provided by macOS to define and manage background services in an application.