Add CalendarAstronomer visibility for WallpaperPicker2 am: 6b763dd0d0

Original change: https://android-review.googlesource.com/c/platform/external/icu/+/2179317

Change-Id: I61d51cd8cfbc45aba6e8af452ba66bfd39b0de26
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>