fix: update hardcoded start date literals in tests to use DEFAULT_START_DATE

Tests were asserting against the literal `2030-01-01` value instead of
importing the constant, causing failures after the default was updated to 2040.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: feanil

cms/djangoapps/contentstore/rest_api/v1/views/tests/test_proctoring.py

@@ -15,6 +15,7 @@
 from cms.djangoapps.contentstore.tests.utils import CourseTestCase
 from openedx.core import toggles as core_toggles
 from openedx.core.djangoapps.course_apps.toggles import EXAMS_IDA
+from xmodule.course_metadata_utils import DEFAULT_START_DATE
 from xmodule.modulestore.django import (
     modulestore,
 )  # lint-amnesty, pylint: disable=wrong-import-order
@@ -61,7 +62,7 @@ def get_expected_response_data(
                 "proctoring_escalation_email": course.proctoring_escalation_email,
                 "create_zendesk_tickets": course.create_zendesk_tickets,
             },
-            "course_start_date": "2030-01-01T00:00:00Z",
+            "course_start_date": DEFAULT_START_DATE.strftime('%Y-%m-%dT%H:%M:%SZ'),
             "available_proctoring_providers": ["null"],
             "requires_escalation_email_providers": [],
         }
@@ -100,7 +101,7 @@ def test_providers_with_disabled_lti(self):
                 "proctoring_escalation_email": self.course.proctoring_escalation_email,
                 "create_zendesk_tickets": self.course.create_zendesk_tickets,
             },
-            "course_start_date": "2030-01-01T00:00:00Z",
+            "course_start_date": DEFAULT_START_DATE.strftime('%Y-%m-%dT%H:%M:%SZ'),
             "available_proctoring_providers": ["null"],
             "requires_escalation_email_providers": [],
         }
@@ -123,7 +124,7 @@ def test_providers_with_enabled_lti(self):
                 "proctoring_escalation_email": self.course.proctoring_escalation_email,
                 "create_zendesk_tickets": self.course.create_zendesk_tickets,
             },
-            "course_start_date": "2030-01-01T00:00:00Z",
+            "course_start_date": DEFAULT_START_DATE.strftime('%Y-%m-%dT%H:%M:%SZ'),
             "available_proctoring_providers": ["lti_external", "null"],
             "requires_escalation_email_providers": ["lti_external"],
         }

cms/djangoapps/contentstore/signals/tests/test_handlers.py

@@ -12,6 +12,7 @@
 from xmodule.modulestore.edit_info import EditInfoMixin
 from xmodule.modulestore.django import SignalHandler
 from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
+from xmodule.course_metadata_utils import DEFAULT_START_DATE
 from xmodule.modulestore.tests.factories import SampleCourseFactory
 
 
@@ -34,7 +35,7 @@ def setUp(self):
             course_key=CourseLocator(org='TestU', course='sig101', run='Summer2022', branch=None, version_guid=None),
             name='Signals 101',
             schedule_data=CourseScheduleData(
-                start=datetime.fromisoformat('2030-01-01T00:00+00:00'),
+                start=DEFAULT_START_DATE,
                 pacing='instructor',
                 end=None,
                 enrollment_start=None,

cms/djangoapps/contentstore/views/tests/test_block.py

@@ -606,11 +606,11 @@ def test_create_block_negative(self):
         self.assertEqual(resp.status_code, 200)
 
     def test_create_with_future_date(self):
-        self.assertEqual(self.course.start, datetime(2030, 1, 1, tzinfo=UTC))
+        self.assertEqual(self.course.start, DEFAULT_START_DATE)
         resp = self.create_xblock(category="chapter")
         usage_key = self.response_usage_key(resp)
         obj = self.get_item_from_modulestore(usage_key)
-        self.assertEqual(obj.start, datetime(2030, 1, 1, tzinfo=UTC))
+        self.assertEqual(obj.start, DEFAULT_START_DATE)
 
     def test_static_tabs_initialization(self):
         """
@@ -3408,7 +3408,7 @@ def validate_chapter_xblock_info(self, xblock_info, has_child_info=True):
             xblock_info["course_graders"],
             ["Homework", "Lab", "Midterm Exam", "Final Exam"],
         )
-        self.assertEqual(xblock_info["start"], "2030-01-01T00:00:00Z")
+        self.assertEqual(xblock_info["start"], DEFAULT_START_DATE.strftime('%Y-%m-%dT%H:%M:%SZ'))
         self.assertEqual(xblock_info["graded"], False)
         self.assertEqual(xblock_info["due"], None)
         self.assertEqual(xblock_info["format"], None)