Use os.scandir instead of os.listdir

It's simpler and better suited for use cases introduced in later commits.

src/documents/consumer.py

@@ -71,8 +71,7 @@ class Consumer:
         })
 
     def run(self):
-        docs = [os.path.join(self.consume, entry)
-                for entry in os.listdir(self.consume)]
+        docs = [entry.path for entry in os.scandir(self.consume)]
         docs_old_to_new = sorted(docs, key=lambda doc: os.path.getmtime(doc))
 
         for doc in docs_old_to_new: