Revert "redbull: update BOARD_API_LEVEL to T" am: ecd9d22132 am: dab4e08530 am: e177aa67d4

Original change: https://googleplex-android-review.googlesource.com/c/device/google/redbull/+/22788402

Change-Id: Id57e9e91b5329b92c46caf24ae02dada8c485809
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>