Update doctest to version 2.4.12 #4697

Job	Run time
codespell	26s
copyright_check	13s
examples_clang-format	14s
examples_ubuntu-22.04_g++_cxx17_release_preview=ON	3m 24s
python_module_test_ubuntu_latest	50s
examples_windows_cl2022_cxx17_relwithdebinfo_preview=OFF	3m 17s
doc_examples_ubuntu-latest_g++_cxx20_relwithdebinfo	1m 0s
examples_windows_11_arm_cl2022_cxx14_relwithdebinfo_preview=ON	3m 20s
examples_ubuntu-24.04_g++_cxx20_debug_preview=ON	3m 26s
macos-15_clang++_cxx17_debug_preview=ON	3m 28s
macos-14_clang++_cxx14_relwithdebinfo_preview=ON	3m 31s
ubuntu-24.04-arm_g++-14_cxx20_debug_preview=ON	3m 22s
ubuntu-22.04_g++_cxx17_release_preview=ON	3m 24s
examples_macos-15_clang++_cxx14_relwithdebinfo_preview=ON	3m 27s
macos-13_clang++_cxx20_release_preview=ON-DBUILD_SHARED_LIBS=OFF	3m 17s
examples_ubuntu-latest_g++_cxx14_relwithdebinfo_preview=OFF	3m 24s
windows_cl2022_cxx14_relwithdebinfo_preview=ON	2m 47s
windows_cl2022_cxx17_relwithdebinfo_preview=OFF	2m 33s
doc_examples_windows-2022_cl_cxx20_relwithdebinfo	1m 27s
windows_11_arm_cl2022_cxx20_release_preview=ON-DBUILD_SHARED_LIBS=OFF	2m 39s
ubuntu-latest_g++_cxx14_relwithdebinfo_preview=OFF	3m 24s
ubuntu-22.04-arm_g++_cxx20_release_preview=ON-DBUILD_SHARED_LIBS=OFF	3m 22s
ubuntu-24.04-arm_clang++_cxx20_release_preview=ON	3m 21s
pages	-1s
documentation	-1s
	59m 34s

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