fix install test error with user with umask other than 0022

[zhw2101024]

Fixes #11363

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/date/date-locale-hour (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/date/resolution (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/pr/bounded-memory (fails in this run but passes in the 'main' branch)
Note: The gnu test tests/cut/cut-huge-range is now being skipped but was previously passing.

[abendrothj]

Thanks for digging into this and opening a fix! While looking at this issue more closely, it turns out there's also an underlying implementation bug: GNU install calls umask(0) at startup so ancestor directories always land at exactly 0755, but uutils doesn't, meaning restrictive umasks like 0027 or 0111 produce wrong ancestor modes beyond just the test failure you caught. Filed that as #12714 and opened #12715 to fix both the implementation and replace the probe-based assertions with the correct assert_eq!(0o40_755) checks. Hopefully useful context!

[zhw2101024]

Thanks for digging into this and opening a fix! While looking at this issue more closely, it turns out there's also an underlying implementation bug: GNU install calls umask(0) at startup so ancestor directories always land at exactly 0755, but uutils doesn't, meaning restrictive umasks like 0027 or 0111 produce wrong ancestor modes beyond just the test failure you caught. Filed that as #12714 and opened #12715 to fix both the implementation and replace the probe-based assertions with the correct assert_eq!(0o40_755) checks. Hopefully useful context!

Excellent work, I'll close this issue and the related PR then.