add function to process all games for rating

src/ratings.py

@@ -118,11 +118,11 @@ def get_current_variant_rating(variant_id: int, num_players: int) -> float:
     return base_rating
 
 
-def process_rating_of_next_game():
+def process_rating_of_next_game() -> bool:
     game_id = next_game_to_rate()
     if game_id is None:
         logger.verbose("All games already processed for rating changes.")
-        return
+        return False
     logger.verbose("Processing rating for game {}".format(game_id))
     cur = conn_manager.get_new_cursor()
 
@@ -180,3 +180,14 @@ def process_rating_of_next_game():
         user_ratings_vals
     )
     conn_manager.get_connection().commit()
+    return True
+
+
+def process_rating_of_all_games():
+    # It might seem a bit tedious of processing every single game separately,
+    # which means reading and writing to the database more than we would strictly need.
+    # However, since we have such a small number of games, this is fast enough without problems,
+    # and makes the program structure easier, therefore avoiding mistakes and improving granularity
+    # of our database updates.
+    while process_rating_of_next_game():
+        pass