Use libc::UTIME_NOW in touch when updating time to now

[iburaky2]

Fixes #9844.

Current uu-touch explicitly provides the current time when updating time to now.

Time PR makes it use libc::UTIME_NOW instead on unix platforms, which requires lower permissions than explicitly providing time. See utimensat.

[sylvestre]

fails with:

error[E0433]: failed to resolve: use of undeclared crate or module `libc`
   --> src/uu/touch/src/touch.rs:384:55
    |
384 |                     now = FileTime::from_unix_time(0, libc::UTIME_NOW as u32);
    |                                                       ^^^^ use of undeclared crate or module `libc`
    |
help: consider importing this crate
    |
11  + use uucore::libc;
    |

For more information about this error, try `rustc --explain E0433`.

[sylvestre]

fails now on windows

[github-actions]

GNU testsuite comparison:

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[github-actions]

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GNU testsuite comparison:

Note: The gnu test tests/printf/printf-surprise is now being skipped but was previously passing.

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/misc/tee (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/tty/tty-eof is no longer failing!

[github-actions]

GNU testsuite comparison:

Note: The gnu test tests/cp/cp-a-selinux was skipped on 'main' but is now failing.