[nrf noup] twister: fix linter issue in blackbox tests

Change also in upstream in PR #78716, but with many
other changes.

Signed-off-by: Grzegorz Chwierut <[email protected]>

Author: gchwier

scripts/tests/twister_blackbox/test_coverage.py

@@ -13,6 +13,7 @@
 import sys
 import json
 
+# pylint: disable=no-name-in-module
 from conftest import TEST_DATA, ZEPHYR_BASE, testsuite_filename_mock, clear_log_in_test
 from twisterlib.testplan import TestPlan