cp: Use PathBuf instead of String for paths

[tmccombs]

I think this should avoid unnecessarily validating utf-8, and avoids a few allocations.

[github-actions[bot]]

GNU testsuite comparison:

GNU test failed: tests/tail-2/inotify-dir-recreate. tests/tail-2/inotify-dir-recreate is passing on 'main'. Maybe you have to rebase?

[tertsdiepraam]

Good idea! Could you add a small test for this with some invalid utf-8, so we don't regress?

[tmccombs]

Sure.

[github-actions[bot]]

GNU testsuite comparison:

GNU test failed: tests/tail-2/inotify-dir-recreate. tests/tail-2/inotify-dir-recreate is passing on 'main'. Maybe you have to rebase?

[github-actions[bot]]

GNU testsuite comparison:

GNU test failed: tests/tail-2/inotify-dir-recreate. tests/tail-2/inotify-dir-recreate is passing on 'main'. Maybe you have to rebase?

[github-actions[bot]]

GNU testsuite comparison:

Congrats! The gnu test tests/tail-2/inotify-dir-recreate is no longer failing!

[jfinkels]

Looks like some test failures on macos and windows

[github-actions[bot]]

GNU testsuite comparison:

GNU test failed: tests/rm/rm2. tests/rm/rm2 is passing on 'main'. Maybe you have to rebase?

[tmccombs]

hmm, it appears that mac won't actually let you create a file with an invalid utf-8 file name, and from some quick research windows might be similar? For now I've just restricted the tests to linux.

[github-actions[bot]]

GNU testsuite comparison:

GNU test failed: tests/tail-2/inotify-dir-recreate. tests/tail-2/inotify-dir-recreate is passing on 'main'. Maybe you have to rebase?

[github-actions[bot]]

GNU testsuite comparison:

GNU test failed: tests/misc/timeout. tests/misc/timeout is passing on 'main'. Maybe you have to rebase?