You'll need to do an Advanced Scan on a package to identify if there is a problem with the artifact. In the Xray Scans List menu navigate to the artifact and navigate to the Security Issues -> Secrets item in the dropdown:
If there is an exposed secret, it will be listed in this menu with the file paths within the impacted artifact:
If there is an exposed secret, it will be listed in this menu with the file paths within the impacted artifact: