WR441709: Fix unit test failure caused by core_calendar

[MichaelReyesCatcan]

1) core_calendar\container_test::test_delete_module_delete_events
coding_exception: Coding error detected, it must be fixed by a programmer: either 'questionpool' or 'questionpoolnamed' property must be specified when generating an adaptive quiz instance

/var/www/site/mod/adaptivequiz/tests/generator/lib.php:45
/var/www/site/calendar/tests/container_test.php:476
/var/www/site/lib/phpunit/classes/advanced_testcase.php:80