feat: reimagine certificate display settings

The course settings `certificate_available_date` (CAD) and
`certificates_display_behavior` (CDB) were previously acting indedependantly
of one another. They now work in tandem. This change:
- limits CDB to a dropdown
- removes "early_with_info" and adds "end_with_date"
- only takes CAD into account if "end_with_date" is selected
- Moves CDB to the main course schedule settings page
- updates CourseOverview to validate these fields and choose sane
defaults if they aren't expected values

Certificates will now show under the following circumstances:
"Immediately upon passing"
certificate_availability_date = null
certificates_display_behavior = "early_no_info"

"End date of course"
certificate_availability_date = null
certificates_display_behavior = "end"

"A date after the course end date"
certificate_availability_date = <date>
certificates_display_behavior = "end_with_date"

openedx/core/djangoapps/programs/tests/test_tasks.py

@@ -30,6 +30,7 @@ from openedx.core.djangoapps.oauth_dispatch.tests.factories import ApplicationFa
 from openedx.core.djangoapps.programs import tasks
 from openedx.core.djangoapps.site_configuration.tests.factories import SiteConfigurationFactory, SiteFactory
 from openedx.core.djangolib.testing.utils import skip_unless_lms
+from xmodule.data import CertificatesDisplayBehaviors
 
 log = logging.getLogger(__name__)
 
@@ -520,6 +521,7 @@ class AwardCourseCertificatesTestCase(CredentialsApiConfigMixin, TestCase):
         self.course = CourseOverviewFactory.create(
             self_paced=True,  # Any option to allow the certificate to be viewable for the course
             certificate_available_date=self.available_date,
+            certificates_display_behavior=CertificatesDisplayBehaviors.END_WITH_DATE
         )
         self.student = UserFactory.create(username='test-student')
         # Instantiate the Certificate first so that the config doesn't execute issuance

openedx/core/djangoapps/programs/tests/test_utils.py

@@ -51,6 +51,7 @@ from openedx.core.djangoapps.site_configuration.tests.factories import SiteFacto
 from openedx.core.djangolib.testing.utils import skip_unless_lms
 from common.djangoapps.student.tests.factories import AnonymousUserFactory, CourseEnrollmentFactory, UserFactory
 from common.djangoapps.util.date_utils import strftime_localized
+from xmodule.data import CertificatesDisplayBehaviors
 from xmodule.modulestore.django import modulestore
 from xmodule.modulestore.tests.django_utils import (
     ModuleStoreTestCase, SharedModuleStoreTestCase, TEST_DATA_SPLIT_MODULESTORE
@@ -499,7 +500,7 @@ class TestProgramProgressMeter(ModuleStoreTestCase):
             end=two_days_ago,
             self_paced=False,
             certificate_available_date=tomorrow,
-            certificates_display_behavior='end'
+            certificates_display_behavior=CertificatesDisplayBehaviors.END_WITH_DATE
         )
         third_course_run_key = str(course3.id)
 
@@ -607,6 +608,7 @@ class TestProgramProgressMeter(ModuleStoreTestCase):
         # 3 certs, all available, program cert in the past/now
         course3_overview = CourseOverview.get_from_id(course3.id)
         course3_overview.certificate_available_date = yesterday
+        course3_overview.certificates_display_behavior = CertificatesDisplayBehaviors.END_WITH_DATE
         course3_overview.save()
         meter = ProgramProgressMeter(self.site, self.user)
         self._assert_progress(
@@ -622,7 +624,7 @@ class TestProgramProgressMeter(ModuleStoreTestCase):
     def test_old_course_runs(self, mock_get_programs):
         """
         Test that old course runs may exist for a program which do not exist in LMS.
-        In that case, continue considering the course run to've been failed by the learner
+        In that case, continue considering the course run to have been failed by the learner
         """
         course_run = CourseRunFactory.create()
         course = CourseFactory.create(course_runs=[course_run])