Update true/false help message to start with Usage:

[dhr412]

Closes #10279

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/tail/follow-name. tests/tail/follow-name is passing on 'main'. Maybe you have to rebase?

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will degrade performance by 3.64%

_{Comparing dhr412:usage-true-false (dc2ffde) with main (d943324)}

Summary

⚡ 9 improved benchmarks
❌ 1 regressed benchmark
✅ 272 untouched benchmarks
⏩ 38 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Memory	sort_long_line[160000]	983.9 KB	712.6 KB	+38.06%
⚡	Memory	sort_ascii_only[500000]	28.3 MB	22.2 MB	+27.83%
⚡	Memory	sort_mixed_data[500000]	27.1 MB	22.9 MB	+18.63%
⚡	Memory	sort_accented_data[500000]	28.3 MB	22.1 MB	+27.86%
⚡	Memory	sort_key_field[500000]	51.8 MB	47.8 MB	+8.25%
⚡	Memory	sort_numeric[500000]	79.2 MB	75.5 MB	+4.9%
⚡	Memory	sort_case_sensitive[500000]	17.4 MB	16.9 MB	+3.02%
⚡	Memory	sort_unique_locale[500000]	39.8 MB	33.6 MB	+18.36%
❌	Memory	dd_copy_default	126 KB	130.8 KB	-3.64%
⚡	Memory	du_wide_tree[(5000, 500)]	1.3 MB	1.2 MB	+6.04%

Footnotes

1. 38 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. ↩

[sylvestre]

I don't think it should be in uucore

[dhr412]

Where would you recommend placing these changes instead?

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/tty/tty-eof (fails in this run but passes in the 'main' branch)