GH-46439: [C++] Remove unneeded namespace prefix in test_util_internal.h#46695

kou merged 1 commit intoapache:mainapache/arrow:mainfrom

amoeba:fix/GH-46439--post-merge-expose-fromjson--remove-nsamoeba/arrow:fix/GH-46439--post-merge-expose-fromjson--remove-nsCopy head branch name to clipboard