Use startActivityAsUser instead of startActivity API to start the AppLocalePickerActivity of different users
Bug: 274378136
Test: 1. Perform AppLocalePickerActivityTest robolectric test
2. Perform the manual test by switching different users
3. Perform the manual test by switching different profiles
Change-Id: I4405b3b7e832b71b9ef66fa71d9e42ce12da167c