Fix puffin failure on duplicating deflates am: 7949fcebaa am: 230231dac2

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/3001037

Change-Id: I10f1b6aed8749ad4ed93627346a70a5d0b181ff5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>