Use ASSERT_* instead of EXPECT_* to abort test early am: e53a318729 am: 0870c30271

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/2803168

Change-Id: I9158b00ce39a8c880058e41df7022936385e4d08
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>