libnm: add nm_utils_uuid_is_null() helper

4 jobs for th/uuid in 14 minutes and 52 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Test
passed #37056
allowed to fail
checkpatch

00:01:24

passed #37057
f28_build_default

00:14:14

passed #37058
f28_rpm_autotools_dbg

00:14:51

passed #37059
f28_rpm_meson_dbg

00:11:36