Add a dedicated RQ queue for exports.

Refs https://redmine.teklia.com/issues/5584

The export tasks should run on a dedicated RQ queue so we can separate them from other tasks in production to run on servers with large HDDs

arkindex/documents/api/ml.py

 import uuid
+from textwrap import dedent
 
 from django.db import transaction
 from django.utils.functional import cached_property
@@ -300,16 +301,22 @@ class CorpusMLClassPagination(PageNumberPagination):
 @extend_schema_view(
     get=extend_schema(
         operation_id="ListCorpusMLClasses",
+        description=dedent("""
+            List available classes in a corpus.
+
+            Requires a **guest** access to the corpus.
+        """),
     ),
     post=extend_schema(
         operation_id="CreateMLClass",
-        description="Create an ML class in a corpus",
+        description=dedent("""
+            Create an ML class in a corpus.
+
+            Requires an **admin** access to the corpus.
+        """),
     )
 )
 class CorpusMLClassList(CorpusACLMixin, ListCreateAPIView):
-    """
-    List available classes in a corpus
-    """
     serializer_class = MLClassSerializer
     pagination_class = CorpusMLClassPagination
     # For OpenAPI type discovery: a corpus ID is in the path
@@ -322,7 +329,7 @@ class CorpusMLClassList(CorpusACLMixin, ListCreateAPIView):
     def corpus(self):
         role = Role.Guest
         if self.request.method == "POST":
-            role = Role.Contributor
+            role = Role.Admin
         return self.get_corpus(self.kwargs["pk"], role=role)
 
     def check_permissions(self, *args, **kwargs):
@@ -357,10 +364,26 @@ class CorpusMLClassList(CorpusACLMixin, ListCreateAPIView):
 
 @extend_schema(tags=["classifications"])
 @extend_schema_view(
-    get=extend_schema(description="Retrieve a ML class."),
-    patch=extend_schema(description="Rename a ML class."),
-    put=extend_schema(description="Rename a ML class."),
-    delete=extend_schema(description="Delete a ML class if it is not used by any classification."),
+    get=extend_schema(description=dedent("""
+        Retrieve an ML class.
+
+        Requires a **guest** access to the corpus.
+    """)),
+    patch=extend_schema(description=dedent("""
+        Rename an ML class.
+
+        Requires an **admin** access to the corpus.
+    """)),
+    put=extend_schema(description=dedent("""
+        Rename an ML class.
+
+        Requires an **admin** access to the corpus.
+    """)),
+    delete=extend_schema(description=dedent("""
+        Delete an ML class if it is not used by any classification.
+
+        Requires an **admin** access to the corpus.
+    """)),
 )
 class MLClassRetrieve(CorpusACLMixin, RetrieveUpdateDestroyAPIView):
     serializer_class = MLClassSerializer
@@ -372,7 +395,7 @@ class MLClassRetrieve(CorpusACLMixin, RetrieveUpdateDestroyAPIView):
     def corpus(self):
         role = Role.Guest
         if self.request and self.request.method != "GET":
-            role = Role.Contributor
+            role = Role.Admin
 
         return self.get_corpus(self.kwargs["corpus"], role=role)