Merge "Give an error when trying to build "next" targets" into main am: 23a778b3 am: 773e7461

Original change: https://android-review.googlesource.com/c/platform/build/+/2703313



Change-Id: I65fa16e7210477652428a97c98d4f675c146f8c3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>