ci : disable fast-math for Metal GHA CI (#14478) #7

Job	Run time
ubuntu-22-vulkan	6m 15s
ubuntu-22-cpu (x64, ubuntu-22.04)	3m 29s
macOS-arm64	2m 15s
windows-cuda (12.4)	41m 41s
windows-cpu (arm64)	4m 12s
windows-cpu (x64)	6m 33s
windows (opencl-adreno, arm64, -G "Ninja Multi-Config" -D CMAKE_TOOLCHAIN_FILE=cmake/arm64-window...	3m 44s
ios-xcode-build	12m 30s
windows-sycl	11m 21s
windows (vulkan, x64, -DGGML_VULKAN=ON, ggml-vulkan)	6m 0s
windows-hip (radeon, gfx1100;gfx1101;gfx1102;gfx1030;gfx1031;gfx1032)	50m 27s
macOS-x64	4m 42s
release	1m 4s
	2h 34m 13s

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