git: openjdk/jdk25u: master: 8369226: GHA: Switch to MacOS 15

[Aleksey Shipilev]

Changeset: 667daee3
Branch: master
Author:    Aleksey Shipilev <shade at openjdk.org>
Date:      2025-10-13 07:45:05 +0000
URL:       https://git.openjdk.org/jdk25u/commit/667daee3683897956d2af755b28e9376a664cb75

8369226: GHA: Switch to MacOS 15

Backport-of: 1ea8cfa6dc8e6f96fd87553331abaae17ec173ea

! .github/workflows/main.yml