cmake: Fix version.h build rule #34

Job	Run time
clang-format	4m 9s
build_test (LLVM 14, Debug, .#bpftrace-llvm14, biosnoop.bt)	16m 19s
build_test (LLVM 15, Debug, .#bpftrace-llvm15, biosnoop.bt)	16m 22s
build_test (LLVM 16, Debug, .#bpftrace-llvm16, biosnoop.bt)	16m 33s
build_test (LLVM 17, Debug, .#bpftrace-llvm17, biosnoop.bt)	16m 19s
build_test (LLVM 18, Debug, .#bpftrace-llvm18, biosnoop.bt)	16m 37s
build_test (LLVM 19 Release, Release, .#bpftrace-llvm19, biosnoop.bt)	16m 4s
build_test (LLVM 19 Debug, Debug, .#bpftrace-llvm19, biosnoop.bt)	16m 25s
build_test (LLVM 19 Clang Debug, Debug, .#bpftrace-llvm19, clang, clang++, biosnoop.bt)	16m 0s
build_test (AOT (LLVM 19 Debug), Debug, .#bpftrace-llvm19, 0, 1, .github/include/aot_skip.txt)	9m 55s
build_test (Memleak test (LLVM 19 Debug), Debug, .#bpftrace-llvm19, 1, 0)	7m 3s
build_test (Memleak test (LLVM 19 Release), Release, .#bpftrace-llvm19, 1, 0)	8m 48s
irc	0s
	2h 40m 34s

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