fix: macro should use snake_case

[xtqqczze]

No description provided.

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/tail/tail-n0f (passes in this run but fails in the 'main' branch)
Note: The gnu test tests/seq/seq-epipe is now being skipped but was previously passing.
Note: The gnu test tests/tail/pipe-f is now being skipped but was previously passing.

[codspeed-hq]

Merging this PR will not alter performance

✅ 285 untouched benchmarks
⏩ 70 skipped benchmarks¹

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_{Comparing xtqqczze:macro-snake-case (da5be7e) with main (52e1bc1)}

Footnotes

1. 70 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[cakebaker]

Thanks!