Mitchell Hashimoto 5b9f4acbc8 ci: update macOS builders to Sequoia (15) and Xcode 16.4
We have been building on macOS 14 and Xcode 16.0 for a longggg time now.
This gets us to a version that will be running Xcode 26 eventually so
we can ultimately build for Tahoe on a stable OS.

This should change nothing in the interim.
2025-06-14 12:32:48 -07:00
..
2023-09-28 10:42:38 -07:00
2025-01-30 13:58:17 -08:00