List available simulators with xcrun simctl list devices available
If one is booted already, use that. Prefer iPhone xx Pros, the latest ones
Run the unit tests with xcodebuild test -project YourApp.xcodeproj -scheme YourScheme -destination 'platform=iOS Simulator,name=iPhone 17 Pro'. The app is usually in the root of the directory. The simulator is the one from step 2. The scheme has to be found out
