This option had originally been added in D83069 to allow disabling the
check that something is going to get run at all when a specific test name
is used on the command-line. Since we now use getTestsForPath() (from D151664)
to get the tests to run for a specific path, we don't need a specific check
for this anymore -- Lit will produce the same complaint it would produce if
you provided a directory with no tests.
If one needs to run a specific test on the command-line and the Lit
configuration would normally not include that test, the configuration
should be set up as a "standalone" configuration or it should be fixed
to allow for that test to be found (i.e. probably fix the allowed test
suffixes).
Needs to be updated.