GREG-25: Adding namespace versioning

Adding namespace-versioning to API.

The swagger interface has been checked and it still works.

It is now possible to look at at a variable in the request (request.version) to inspect the namespace used.

greg/urls.py

@@ -16,9 +16,25 @@ Including another URLconf
 from typing import List
 from django.urls import path, include
 from django.urls.resolvers import URLResolver
+from drf_spectacular.views import SpectacularAPIView, SpectacularSwaggerView
+from rest_framework.versioning import NamespaceVersioning
 
 from greg.api import urls as api_urls
+from greg.api.views.health import Health
 
 urlpatterns: List[URLResolver] = [
-    path("api/", include(api_urls.urlpatterns)),
+    path(
+        "schema/",
+        SpectacularAPIView.as_view(versioning_class=NamespaceVersioning),
+        name="schema",
+    ),  # type: ignore
+    path(
+        "schema/swagger-ui/",
+        SpectacularSwaggerView.as_view(
+            url_name="schema", versioning_class=NamespaceVersioning
+        ),  # type: ignore
+        name="swagger-ui",
+    ),
+    path("health/", Health.as_view()),  # type: ignore
+    path("api/v1/", include((api_urls.urlpatterns, "greg"), namespace="v1")),
 ]