[BD-14] Migrate all environments to use database-backed organizations (#25153)

* Install `organizations` app into LMS and Studio non-optionally.
* Add toggle `ORGANIZATIONS_AUTOCREATE` to Studio.
* Remove the `FEATURES["ORGANIZATIONS_APP"]` toggle.
* Use the new `organizations.api.ensure_organization` function to
  either validate or get-or-create organizations, depending
  on the value of `ORGANIZATIONS_AUTOCREATE`,
  when creating course runs and V2 content libraries.
  We'll soon use it for V1 content libraries as well.
* Remove the `util.organizations_helpers` wrapper layer
  that had to exist because `organizations` was an optional app.
* Add `.get_library_keys()` method to the Split modulestore.
* Add Studio management command for backfilling organizations tables
  (`backfill_orgs_and_org_courses`).

For full details, see
https://github.com/edx/edx-organizations/blob/master/docs/decisions/0001-phase-in-db-backed-organizations-to-all.rst

TNL-7646

openedx/core/djangoapps/content_libraries/views.py

@@ -10,6 +10,8 @@ from django.shortcuts import get_object_or_404
 from django.utils.translation import ugettext as _
 import edx_api_doc_tools as apidocs
 from opaque_keys.edx.locator import LibraryLocatorV2, LibraryUsageLocatorV2
+from organizations.api import ensure_organization
+from organizations.exceptions import InvalidOrganizationException
 from organizations.models import Organization
 from rest_framework import status
 from rest_framework.exceptions import NotFound, PermissionDenied, ValidationError
@@ -156,14 +158,17 @@ class LibraryRootView(APIView):
         # definitions elsewhere.
         data['library_type'] = data.pop('type')
         data['library_license'] = data.pop('license')
-        # Get the organization short_name out of the "key.org" pseudo-field that the serializer added:
-        org_name = data["key"]["org"]
         # Move "slug" out of the "key.slug" pseudo-field that the serializer added:
         data["slug"] = data.pop("key")["slug"]
+        # Get the organization short_name out of the "key.org" pseudo-field that the serializer added:
+        org_name = data["key"]["org"]
         try:
-            org = Organization.objects.get(short_name=org_name)
-        except Organization.DoesNotExist:
-            raise ValidationError(detail={"org": "No such organization '{}' found.".format(org_name)})
+            ensure_organization(org_name)
+        except InvalidOrganizationException:
+            raise ValidationError(
+                detail={"org": "No such organization '{}' found.".format(org_name)}
+            )
+        org = Organization.objects.get(short_name=org_name)
         try:
             result = api.create_library(org=org, **data)
         except api.LibraryAlreadyExists: