Add GCC 12.5 for Bullseye #156

Job	Run time
build (linux/amd64, ubuntu-24.04, bullseye, gcc, 12)	1h 31m 23s
build (linux/amd64, ubuntu-24.04, bookworm, gcc, 14)	1m 54s
build (linux/amd64, ubuntu-24.04, bookworm, clang, 17)	1m 53s
build (linux/amd64, ubuntu-24.04, bookworm, clang, 19)	1m 50s
build (linux/amd64, ubuntu-24.04, bookworm, clang, 18)	1m 59s
build (linux/amd64, ubuntu-24.04, bookworm, gcc, 13)	2m 21s
build (linux/amd64, ubuntu-24.04, bookworm, clang, 20)	1m 43s
build (linux/arm64, ubuntu-24.04-arm, bookworm, gcc, 12)	1m 57s
build (linux/amd64, ubuntu-24.04, bookworm, gcc, 12)	1m 50s
build (linux/arm64, ubuntu-24.04-arm, bullseye, gcc, 12)	59m 8s
build (linux/arm64, ubuntu-24.04-arm, bookworm, clang, 20)	2m 6s
build (linux/arm64, ubuntu-24.04-arm, bookworm, gcc, 15)	2m 32s
build (linux/arm64, ubuntu-24.04-arm, bookworm, gcc, 14)	2m 7s
build (linux/arm64, ubuntu-24.04-arm, bookworm, clang, 17)	1m 56s
build (linux/arm64, ubuntu-24.04-arm, bookworm, clang, 16)	1m 49s
build (linux/arm64, ubuntu-24.04-arm, bookworm, gcc, 13)	2m 4s
build (linux/arm64, ubuntu-24.04-arm, bookworm, clang, 19)	2m 19s
build (linux/amd64, ubuntu-24.04, bookworm, clang, 16)	1m 49s
build (linux/arm64, ubuntu-24.04-arm, bookworm, clang, 18)	2m 7s
build (linux/amd64, ubuntu-24.04, bookworm, gcc, 15)	1m 54s
merge	-1s
	3h 6m 40s

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