drv.log versus med.log for _cpllog setting in systems tests

[glemieux]

Looking at some of my recent regression tests for ctsm-fates and comparing them to some regression tests on e3sm-fates, I noticed that the MEMLEAK check is returning "Insufficient data for memleak test" for ctsm-fates tests. After some guidance from @billsacks and @ekluzek, I took a look at the system_tests_common.py code and noticed that the _cpllog appears to be defined as drv for nuopc cases. Looking at the log files from the ctsm-fates runs, I don't see much in the drv.log, but I do see a bunch of memory reporting in med.log. Is this correct or is there something that changed since commit 4376e62?