use global namespace for tests

integrationtests/demo_tests/direct_manual_input_test.py

integrationtests/demo_tests/direct_offboard_posctl_test.py

integrationtests/demo_tests/direct_tests.launch

integrationtests/demo_tests/flight_path_assertion.py

integrationtests/demo_tests/manual_input.py

integrationtests/demo_tests/mavros_offboard_attctl_test.py

integrationtests/demo_tests/mavros_offboard_posctl_test.py

integrationtests/demo_tests/mavros_tests.launch