Tests that the attribution is updated if it gets a second attribution with higher priority.


Attributed Private Click Measurements:
WebCore::PrivateClickMeasurement 1
Source site: 127.0.0.1
Attribute on site: localhost
Source ID: 3
Attribution trigger data: 12
Attribution priority: 4
Attribution earliest time to send: Within 24-48 hours
Application bundle identifier: com.apple.WebKit.WebKitTestRunner