Update request base calculated status

Once a requester has asked for a internal review their request's base
status shouldn't ever be `waiting_classification` as this limits the
possible classification statuses.

Returning `internal_review` allows the requester to classify the request
as `I'm still waiting for the internal review` after they receive an
acknowledgement of their review.

Fixes #3830

app/models/info_request.rb

@@ -1020,8 +1020,18 @@ def calculate_status(cached_value_ok=false)
     @cached_calculated_status = @@custom_states_loaded ? theme_calculate_status : base_calculate_status
   end
 
+  def internally_reviewed?
+    outgoing_messages.where(what_doing: 'internal_review').any?
+  end
+
   def base_calculate_status
-    return 'waiting_classification' if awaiting_description
+    if awaiting_description
+      if internally_reviewed?
+        return 'internal_review'
+      else
+        return 'waiting_classification'
+      end
+    end
     return described_state unless described_state == "waiting_response"
     # Compare by date, so only overdue on next day, not if 1 second late
     return 'waiting_response_very_overdue' if