[roottest] improve cmake for `root/collection` #22981

Job	Run time
Windows 10 x64 Release	1h 13m 9s
Windows 10 x86 Release	1h 4m 41s
mac13 ARM64 builtin_zlib=ON	32m 42s
mac14 X64 CMAKE_CXX_STANDARD=20	2h 34m 46s
mac15 ARM64 CMAKE_CXX_STANDARD=23	23m 51s
Upload Event Payload	3s
mac-beta ARM64 CMAKE_CXX_STANDARD=23	41m 20s
fedora43 CMAKE_CXX_STANDARD=23	29m 0s
fedora42 CMAKE_CXX_STANDARD=23	36m 49s
alma9 CMAKE_BUILD_TYPE=Debug	1h 6m 53s
alma8	31m 50s
ubuntu22 imt=Off, CMAKE_BUILD_TYPE=Debug	1h 25m 30s
alma10	27m 39s
ubuntu2510 CMAKE_CXX_STANDARD=23	27m 58s
alma9 modules_off runtime_cxxmodules=Off	25m 32s
alma9 arm64 CMAKE_BUILD_TYPE=RelWithDebInfo, builtin_zlib=ON, builtin_zstd=ON	40m 16s
ubuntu2404 CMAKE_BUILD_TYPE=Debug	1h 22m 45s
ubuntu2504 CMAKE_CXX_STANDARD=23	33m 18s
debian125 CMAKE_CXX_STANDARD=20, dev=ON, CMAKE_CXX_FLAGS=-Wsuggest-override	28m 7s
alma10 clang Ninja CMAKE_C_COMPILER=clang, CMAKE_CXX_COMPILER=clang++	23m 28s
alma9 march_native CMAKE_BUILD_TYPE=RelWithDebInfo, CMAKE_CXX_FLAGS=-march=native, CMAKE_C_FLAGS=-march=native, builtin_zlib=ON, builtin_zstd=ON	27m 8s
rawhide Fedora pydebug CMAKE_CXX_STANDARD=23	35m 33s
	16h 32m 18s

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