runner/runner_tests: Fix name of no-subtests in unit tests

Now that runner normalizes no-subtest entries in testlists, make sure
the name matches what's available.

Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Reviewed-by: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Signed-off-by: Petri Latvala <adrinael@adrinael.net>