Update images to gcc 15 toolchain [postponed] #1878
Description
The following images will be updated to use gcc 15 on 2026-01-03 [postponed]
- manylinux_2_28 (gcc-toolset-14 -> gcc-toolset-15)
- manylinux_2_34 (gcc-toolset-14 -> gcc-toolset-15)
- manylinux_2_29 (gcc-toolset-14 -> gcc-toolset-15)
- musllinux_1_2 (Alpine Linux 3.22 -> Alpine Linux 3.23)