MT#58450 Support and use django-structlog versions >=6.0

As of django-structlog v6.0.0, our django application fails with:

| Traceback (most recent call last):
|   File "/var/lib/repoapi/venv_prod/lib/python3.9/site-packages/django/utils/module_loading.py", line 20, in import_string
|     return getattr(module, class_name)
| AttributeError: module 'django_structlog.middlewares' has no attribute 'CeleryMiddleware'

Quoting from
https://django-structlog.readthedocs.io/en/latest/upgrade_guide.html#upgrading-to-6-0:

| (If you use celery) Make sure you use DJANGO_STRUCTLOG_CELERY_ENABLED = True
|
| It is only applicable if you use celery integration.
|
| django_structlog.middlewares.CeleryMiddleware has been remove in favor of a django settings.
|
| MIDDLEWARE += [
|     "django_structlog.middlewares.RequestMiddleware",
|     # "django_structlog.middlewares.CeleryMiddleware",  # <- remove this
| ]
|
| DJANGO_STRUCTLOG_CELERY_ENABLED = True # <-- add this

Instead of forcing usage of an older django-structlog version,
let's make sure we have 6.0 or newer and update configuration
accordingly.

Change-Id: I0449c05db682ace22438b8b0ad8d8a4a1dfca71a

repoapi/settings/common.py

@@ -60,9 +60,10 @@ MIDDLEWARE = (
     "django.middleware.clickjacking.XFrameOptionsMiddleware",
     "django.middleware.security.SecurityMiddleware",
     "django_structlog.middlewares.RequestMiddleware",
-    "django_structlog.middlewares.CeleryMiddleware",
 )
 
+DJANGO_STRUCTLOG_CELERY_ENABLED = True
+
 ROOT_URLCONF = "repoapi.urls"
 LOGIN_URL = "rest_framework:login"
 LOGOUT_URL = "rest_framework:logout"

requirements/common.txt

@@ -10,7 +10,7 @@ django-extensions
 django-filter
 django-import-export>=3.0
 django-jsonify
-django-structlog
+django-structlog>=6.0
 django-timezone-field
 djangorestframework>=3.6
 djangorestframework-api-key==2.*