tests: remove getmemory() usage on tests

tests: remove getmemory() usage on tests

To check memory leaks, we should use whole program memory analysis tools
such as VLD (on Windows), ASAN (on Linux/macOS) or Valgrind (on Linux/macOS).

Using `test_run(.., .., "mode_nwni_profiling")` will track the memory
on the selected tests without having gross estimate within them.

Change-Id: Ib05b7dbf028fdb13e0a580bb30573b0cf8990efc