ci: Disable MacOS-11 CI (#1746) #2993

Job	Run time
macos-12 appleclang13/C++17 py3.10 MacOS-12	14m 34s
Ubuntu Debug gcc7/C++14 llvm9 py2.7 oiio2.3 exr2.4 sse4 boost1.65 exr2.4	44m 22s
macos-13 appleclang14/C++17 py3.11 MacOS-13	12m 38s
VFX2019 gcc6/C++14 llvm9 py2.7 boost1.66 exr2.4 oiio2.3 sse2	10m 22s
Ubuntu gcc10/C++17 llvm10 oiio-release boost1.65 exr2.5 avx2	6m 58s
VFX2019 clang9/C++14 llvm9 oiio-release boost1.66 avx2 exr2.4 py2.7	7m 2s
Ubuntu latest releases gcc11/C++17 llvm15 boost1.71 exr3.2 py3.9 avx2 batch-b16avx512	48m 45s
VFX2020 gcc6/C++14 llvm10 py3.7 boost1.70 exr2.4 oiio2.2 sse4	8m 54s
Ubuntu bleeding edge gcc12/C++17 llvm16 oiio/ocio/exr/pybind-master boost1.71 py3.10 avx2 batch-b16avx512	17m 54s
VFX2021 gcc9/C++17 llvm11 py3.7 boost1.73 exr2.5 oiio2.3 avx2 batch-b8avx2	18m 53s
Ubuntu clang14/C++17 llvm14 boost1.71 exr3.1 py3.8 avx2 batch-b16avx512	21m 22s
VFX2022 gcc9/C++17 llvm13 py3.9 boost1.76 exr3.1 oiio-rel avx2	22m 6s
VFX2022 clang12/C++17 llvm12 oiio-master boost1.73 exr3.1 py3.9 avx2 batch-avx512	26m 50s
VFX2022 icc/C++17 llvm14 py3.9 boost1.76 exr3.1 oiio-master avx2	24m 14s
VFX2022 icx/C++17 llvm14 py3.9 boost1.76 exr3.1 oiio2.3 avx2	29m 55s
VFX2023 gcc11/C++17 llvm15 py3.10 boost1.80 exr3.1 oiio-rel avx2	28m 24s
VFX2023 GPU Cuda11 gcc11/C++17 llvm15 py3.10 boost1.80 exr3.1 OIIO-master avx2	5m 53s
VFX2019 oldest everything gcc6/C++14 llvm9 py2.7 boost1.66 oiio2.3 no-simd exr2.4	8m 6s
VFX2022 sanitizers	31m 56s
VFX2022 clang-format	4m 19s
	6h 33m 27s

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