Scheduling fails with Drupal Page cache

I suggest more-or-less reverting the change made in 🐛 The Sidewide Alerts load route set a maximum cache max age of 30 in an interesting spot Active as that fixes the problem. I was tempted to just use the `cache_max_age` setting directly here. I'm honestly not 100% sure if it's what we want to do. I've erred on the side of keeping fresher data at the origin and am using 30 seconds, or cache_max_age, whichever is lower.

Thank you for catching this azinck!