SKAdNetwork 관련하여 앱을 업데이트했는데, Branch 대시보드에 테스트 데이터가 표시되지 않습니다.

SKAdNetwork는 모든 당사자가 어트리뷰션을 유저에게 연결할 수 있는 기능을 방지하기 위한 것이므로, Apple은 불명확한 전환 임계값이 퍼블리셔 앱 및 캠페인 ID에 대해 일어나면 광고주로의 변환만 확인합니다.
SKAdNetwork does not attribute conversions in real-time. When the app is installed, a 24 hour rolling timer begins and only when that timer expires, can the install then be attributed after an additional 0-24 hours. Every time an additional conversion is reported with a conversion value greater than the previous value, the 24 hour rolling timer is reset and the install does not get attributed until that 24 hour timer is allowed to expire. Apple offers a developer profile here, that can reduce the timers for testing from 24 hours to 5 minutes.

If your app uses App Clips, any API calls to SKAdNetwork from an app clip’s code will have no effect, return empty strings, or return values that indicate unavailability. See disclaimer at the bottom of Apple's docs here.