allow mobile app to consume internal schedules api endpoints (#2109)

# What this PR does

allow mobile app to consume internal schedules api endpoints

## Checklist

- [ ] Unit, integration, and e2e (if applicable) tests updated
- [ ] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] `CHANGELOG.md` updated (or `pr:no changelog` PR label added if not
required)

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Added
+
+- Allow mobile app to consume "internal" schedules API endpoints by @joeyorlando ([#2109](https://github.com/grafana/oncall/pull/2109))
+
 ## v1.2.39 (2023-06-06)
 
 ### Changed

engine/apps/api/views/schedule.py

@@ -27,6 +27,7 @@ from apps.api.serializers.user import ScheduleUserSerializer
 from apps.auth_token.auth import PluginAuthentication
 from apps.auth_token.constants import SCHEDULE_EXPORT_TOKEN_NAME
 from apps.auth_token.models import ScheduleExportAuthToken
+from apps.mobile_app.auth import MobileAppAuthTokenAuthentication
 from apps.schedules.models import OnCallSchedule
 from apps.slack.models import SlackChannel
 from apps.slack.tasks import update_slack_user_group_for_schedules
@@ -72,7 +73,10 @@ class ScheduleView(
     ModelViewSet,
     mixins.ListModelMixin,
 ):
-    authentication_classes = (PluginAuthentication,)
+    authentication_classes = (
+        MobileAppAuthTokenAuthentication,
+        PluginAuthentication,
+    )
     permission_classes = (IsAuthenticated, RBACPermission)
     rbac_permissions = {
         "metadata": [RBACPermission.Permissions.SCHEDULES_READ],