[v9_16] Ensure dnstap_test returns SKIPPED_TEST_EXIT_CODE
Make sure lib/dns/tests/dnstap_test returns an exit code that indicates
a skipped test when dnstap is not enabled.
(cherry picked from commit c2863417)
To be merged after !4681 (merged).
Make sure lib/dns/tests/dnstap_test returns an exit code that indicates
a skipped test when dnstap is not enabled.
(cherry picked from commit c2863417)
To be merged after !4681 (merged).