rm: fix gnu coreutils test one-file-system.sh

[mattsu2020]

Summary

Remove the extra leading rm: from the rm-error-preserve-root-all locale strings so the message matches expected test output. Keep wording otherwise unchanged across en-US and fr-FR locales.

#9127

[github-actions[bot]]

GNU testsuite comparison:

Congrats! The gnu test tests/rm/one-file-system is no longer failing!

[github-actions[bot]]

GNU testsuite comparison:

Congrats! The gnu test tests/rm/one-file-system is no longer failing!

[github-actions[bot]]

GNU testsuite comparison:

Skipping an intermittent issue tests/tail/overlay-headers (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/rm/one-file-system is no longer failing!

[github-actions[bot]]

GNU testsuite comparison:

Skip an intermittent issue tests/misc/tee (fails in this run but passes in the 'main' branch)
Congrats! The gnu test tests/rm/one-file-system is no longer failing!

[github-actions[bot]]

GNU testsuite comparison:

Skip an intermittent issue tests/misc/tee (fails in this run but passes in the 'main' branch)
Congrats! The gnu test tests/rm/one-file-system is no longer failing!

[codspeed-hq[bot]]

CodSpeed Performance Report

Merging #9428 will degrade performances by 2.36%

_{Comparing mattsu2020:rm_compatibility (01ac5f3) with main (06d843f)}

Summary

❌ 1 regression
✅ 126 untouched
⏩ 6 skipped[^skipped]

:warning: Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
❌	rm_force_files	2 ms	2.1 ms	-2.36%
[^skipped]: 6 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.

[github-actions[bot]]

GNU testsuite comparison:

Skipping an intermittent issue tests/tail/overlay-headers (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/rm/one-file-system is no longer failing!