workflow: add hdrtool in artifact list. #13

Job	Run time
build (ubuntu-24.04-arm, aarch64, clang, clang)	35s
build (windows-11-arm, aarch64, cl, cl)	44s
build (ubuntu-latest, x86_64, clang, clang)	18s
build (windows-latest, x86_64, cl, cl)	25s
build (macos-latest, x86_64, clang, clang)	8s
	2m 10s

Provide feedback