fmq_unit_tests: remove objects form the heap am: cdf8d33b16 am: 6a21b5f737 am: 272fe1e1dd am: 8d0f459682

Original change: https://android-review.googlesource.com/c/platform/system/libfmq/+/2230529

Change-Id: I691242ca0f191ca627fd1415fd9422929dd539b5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>