Course overview block does not honour "coursegraceperiodbefore" and "coursegraceperiodafter"

Steps to reproduce:

• Log in as admin
• Create a course (CourseA) with Course start date 1 month in the future and no end date.
• Create a course (CourseB) with Course start date 1 year in the past and course end date 1 month in the past.
• Enrol a user (User1) on CourseA and CourseB
• Log in as User1 and view the dashboard page.
• In the "Course overview" block, select the "Past" filter
  • CourseB should be displayed
• Select the "Future" filter
  • CourseA should be displayed
• Switch back to admin. In Site administration > Appearance > Courses set "Grace period for future courses" to 60, "Grace period for past courses" to 60, and save changes.
• Switch to User1 and view the dashboard page.
• In the "Course overview" block, CourseA and CourseB should now show when the "In progress" filter is selected, not "Past" or "Future".
• Launch the Moodle app. Connect to the site and log in as User1.
• In the Course overview block, select the In progress filter
  • EXPECTED: CourseA and CourseB are displayed
  • ACTUAL: CourseA and CourseB are not displayed. CourseA appears when Future is selected, and CourseB appears when Past is selected.

This behaviour is due to initCourseFilters() in src/addons/block/myoverview/components/myoverview/myoverview.ts not using the coursegradeperiodbefore and coursegradeperiodafter settings when deciding whether a date is "Past", "Future" or "In progress".

The logic used should be the same as course_classify_for_timeline() in Moodle core's course/lib.php