[cling] Use single `Parser` for `LookupHelper` #15024

Job	Run time
Windows 10 x64 Release	1h 8m 24s
mac13 ARM64 LLVM_ENABLE_ASSERTIONS=On, builtin_zlib=ON	20m 41s
Windows 10 x86 Release	1h 48m 25s
mac14 X64 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	53m 42s
mac15 ARM64 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	26m 58s
Upload Event Payload	5s
mac-beta ARM64 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	36m 42s
fedora40 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	36m 25s
fedora41 LLVM_ENABLE_ASSERTIONS=On	28m 35s
alma8 LLVM_ENABLE_ASSERTIONS=On	44m 43s
alma9 LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	1h 27m 28s
ubuntu22 imt=Off, LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	1h 1m 1s
ubuntu2404 LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	1h 12m 51s
ubuntu2410 LLVM_ENABLE_ASSERTIONS=On, CMAKE_BUILD_TYPE=Debug	1h 13m 17s
debian125 LLVM_ENABLE_ASSERTIONS=On, CMAKE_CXX_STANDARD=20	24m 54s
alma9 modules_off runtime_cxxmodules=Off	21m 45s
alma9 march_native CMAKE_BUILD_TYPE=RelWithDebInfo, CMAKE_CXX_FLAGS=-march=native, CMAKE_C_FLAGS=-march=native, fortran=OFF	38m 37s
alma9-clang clang LLVM_ENABLE_ASSERTIONS=On, CMAKE_C_COMPILER=clang, CMAKE_CXX_COMPILER=clang++	42m 20s
	14h 6m 53s

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