mm test in ubuntu_ltp tend to timeout on AMD64 node amaura

[Po-Hsu Lin]

The test will timeout for the 2 hours threshold

ERROR - 05:54:29 DEBUG| Persistent state client._record_indent now set to 1
ERROR - 05:54:29 DEBUG| Persistent state client.unexpected_reboot deleted
ERROR - 05:54:29 DEBUG| Test has timeout: 7200 sec.
ERROR - 05:54:29 INFO | START ubuntu_ltp.mm ubuntu_ltp.mm timestamp=1562219669 timeout=7200 localtime=Jul 04 05:54:29
ERROR - 05:54:29 DEBUG| Persistent state client._record_indent now set to 2
ERROR - 05:54:29 DEBUG| Persistent state client.unexpected_reboot now set to ('ubuntu_ltp.mm', 'ubuntu_ltp.mm')
ERROR - 05:54:29 DEBUG| Waiting for pid 28858 for 7200 seconds

This is probably related to the oom tests, we need to investigate it to see if we need to skip those oom tests.

Test status across different kernels:
Disco - passed in 11min
Cosmic - timeout
Bionic-hwe-edge - passed in 11min
Bionic - timeout