Mikko Haiku

Instead of using `cohort_get_all_cohorts()` method, which returns only 25 cohorts, this modification fetches all the cohorts straight from the database without limitations.

Cohorts are retrieved here by a call of `cohort_get_all_cohorts()` https://github.com/catalyst/moodle-tool_mfa/blob/MOODLE_400_STABLE/factor/cohort/settings.php#L41 The method retrieves by default only 25 cohorts, as defined here https://github.com/moodle/moodle/blob/6374475dc3cf3a94e22ec18c4655b89819a1b5d6/cohort/lib.php#L498 (cohort_get_all_cohorts($page = 0, $perpage = 25, $search =...