test_mt_dop_fallback appears flaky

custom_cluster/test_mt_dop.py:64: in test_mt_dop_fallback
    self.run_test_case('QueryTest/mt-dop-auto-fallback', vector, use_db=unique_database)
common/impala_test_suite.py:675: in run_test_case
    update_section=pytest.config.option.update_results)
common/test_result_verifier.py:612: in verify_runtime_profile
    actual))
E   AssertionError: Did not find matches for lines in runtime profile:
E   EXPECTED LINES:
E   row_regex:.*All 3 execution backends \(5 fragment instances\) started.*
E   
E   ACTUAL PROFILE:
E   Query (id=ef4c1ba0e5cfa3ad:6f08199100000000):
E     DEBUG MODE WARNING: Query profile created while running a DEBUG build of Impala. Use RELEASE builds to measure query performance.
E     Summary:
E       Session ID: 4d424908616264cd:f776e0e33e5eba9e
E       Session Type: BEESWAX
E       Start Time: 2019-10-22 20:21:42.385801000
E       End Time: 2019-10-22 20:21:46.706553000
E       Query Type: QUERY
E       Query State: FINISHED
E       Query Status: OK
E       Impala Version: impalad version 3.4.0-SNAPSHOT DEBUG (build e05a5323785ecb09e45bdb5dfc96533e68256175)
E       User: jenkins
E       Connected User: jenkins