We don't need need separate unit tests for basic tests that can
just run in the same test-run. If you really need to run only
a particular set of tests, try
  ./src/settings/plugins/ifcfg-rh/tests/test-ifcfg-rh -p /settings/plugins/ifcfg-rh/utils

Results in less compilation (time), and less binaries to test during
`make check`.