[Panlingual] Can't set per-app languages for apps on work profile page

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