MADELINE: Jeremy didn’t call?
LOUISE: Not in a timely manner, no.
MADELINE: Well, good riddance to bad luggage.
Madeline makes a play on the English idiom, “Good riddance to bad rubbish”, meaning that you are better off without that bothersome person or situation. “Good riddance” has been in use since the 16th century, while the “bad rubbish” part was added around the 18th century.
Note that Rory is still reading alone at lunchtime, although she is at least eating at the same table as Madeline and Louise. No sign of Lisa!