Problem 1: not_embedded_server runs SELECT FROM I_S.PROCESSLIST near the beginning.
check_testcase executes a query to the server before that. There is a race here,
because there is no guarantee that the thread executing check_testcase's query is
finished.
Problem 2: The SELECT FROM I_S.PROCESSLIST doens't seem very useful in the test.
It's at least misplaced.
Fix to both problems: Comment out SELECT FROM I_S.PROCESSLIST.