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

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

Change-Id: Iaea87395a3706b4b6d40f671a699d8df19546db9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>