Added updateEngine_downloadAction_fuzzer am: 55fec45931

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/1810483

Change-Id: Ie91c0da6e4739cfb8bdef63378590974654ab8f6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>