chore: Refactor ArangoDB class and script for fetching EV speeches

This commit refactors the ArangoDB class and script for fetching electric vehicle (EV) speeches. The changes improve the efficiency and readability of the code, ensuring a smoother retrieval process for EV speeches.

arango_class.py

@@ -23,12 +23,12 @@ class ArangoDB:
 
     def all_ev_speeches(self):
             """
-            Retrieves all speeches from the 'ev_speeches' collection.
+            Retrieves all EV speeches from the 'ev_speeches' collection.
 
             Returns:
-                A list of all speeches in the 'ev_speeches' collection.
+                A cursor object containing all EV speeches.
             """
-            return list(self.db.collection('ev_speeches').all())
+            return self.db.collection('ev_speeches').all()
 
     def update_ev_document(self, document):
         """