Upgrade to Django 5.2 LTS (#16185)

Upgrade to Django 5.2 LTS with compatibility fixes across fields, migrations, dispatch config, tests, and dev deps.

Dependencies:
- Upgrade django to 5.2.8 and relax requirements.in to >=5.2,<5.3.
- Bump django-debug-toolbar to >=6.0 for compatibility.

Backend:
- awx/conf/fields.py: switch URL TLD regex to use DomainNameValidator.ul in custom URLField.
- awx/main/management/commands/gather_analytics.py: use datetime.timezone.utc for naïve datetime handling.
- awx/main/dispatch/config.py: add mock_publish option; avoid DB access for test runs, set default max_workers, and support a noop broker.

Migrations (SQLite/Postgres compatibility):
- Add awx/main/migrations/_sqlite_helper.py with db-aware AlterIndexTogether/RenameIndex wrappers; consume in 0144_event_partitions.py and 0184_django_indexes.py.
- Update 0187_hop_nodes.py to use CheckConstraint(condition=...).
- Add 0205_alter_instance_peers_alter_job_hosts_and_more.py adjusting through_fields/relations on instance.peers, job.hosts, and role.ancestors.
- _dab_rbac.py: iterate roles with chunk_size=1000 for migration performance.

Tests:
Include hcp_terraform in default credential types in test_credential.py.
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Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Alan Rominger <arominge@redhat.com>

requirements/requirements.txt

@@ -124,7 +124,7 @@ dispatcherd==2025.5.21
     # via -r /awx_devel/requirements/requirements.in
 distro==1.9.0
     # via -r /awx_devel/requirements/requirements.in
-django==4.2.26
+django==5.2.8
     # via
     #   -r /awx_devel/requirements/requirements.in
     #   channels