Replace @CorePlatformApi APIs usages in TimeZoneInfoPreferenceControllerTest

The time zone transitions can be obtained via the public API
ZoneId.getRules() instead.

Bug: 119751170
Test: atest SettingsRoboTests
     com.android.settings.datetime.timezone.TimeZoneInfoPreferenceControllerTest passes
Change-Id: I2c7864580b2a36b725ee250253e97f6cc86d72a4
2 files changed