AddressSanitizer tests broken on Ubuntu 18.04

[leezu]

Description

AddressSanitizer based on the libasan.so fails on Ubuntu 18.04 (but continues to pass on our Ubuntu 16.04 CI).

Keep AddressSanitizer tests on Ubuntu 16.04 for now, but should be fixed

[2020-04-23T18:43:28.149Z] + cd /work/mxnet/build/cpp-package/example/

[2020-04-23T18:43:28.149Z] + /work/mxnet/cpp-package/example/get_data.sh

[2020-04-23T18:43:28.149Z] Downloading http://yann.lecun.com/exdb/mnist/train-images-idx3-ubyte.gz ...

[2020-04-23T18:43:29.072Z] Downloading http://yann.lecun.com/exdb/mnist/train-labels-idx1-ubyte.gz ...

[2020-04-23T18:43:29.327Z] Downloading http://yann.lecun.com/exdb/mnist/t10k-images-idx3-ubyte.gz ...

[2020-04-23T18:43:30.252Z] Downloading http://yann.lecun.com/exdb/mnist/t10k-labels-idx1-ubyte.gz ...

[2020-04-23T18:43:30.252Z] Downloading http://data.mxnet.io/data/mnist_train.csv.gz ...

[2020-04-23T18:43:31.612Z] 

[2020-04-23T18:43:31.612Z] =================================================================

[2020-04-23T18:43:31.612Z] ==6==ERROR: LeakSanitizer: detected memory leaks

[2020-04-23T18:43:31.612Z] 

[2020-04-23T18:43:31.612Z] Direct leak of 2 byte(s) in 1 object(s) allocated from:

[2020-04-23T18:43:31.612Z]     #0 0x7fd76c851f90 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf90)

http://jenkins.mxnet-ci.amazon-ml.com/blue/organizations/jenkins/mxnet-validation%2Fmiscellaneous/detail/PR-18138/10/pipeline

To reproduce (once #18138 is merged), run from the mxnet repo root director:

git clean -ffxd; python ci/build.py --platform ubuntu_cpu /work/runtime_functions.sh build_ubuntu_cpu_cmake_asan; python ci/build.py --platform ubuntu_cpu /work/runtime_functions.sh integrationtest_ubuntu_cpu_asan

[vexilligera]

#18181