By Wyatte Grantham-Philips | The Associated Press Trader Joe’s recently upped the price for a single banana to 23 cents, a 4-cent — or 21% — increase from the Monrovia-based grocer’s previous going rate for the fruit that had remained unchanged for over 20 years. “We only change our prices when our costs change, and after holding our price for bananas at 19¢ each for more than two decades, we’ve now reached a point where this