dd: misc gnu test

[matrixhead]

this fixes the misc test case in dd, it was failing because there was this check in misc where dd should error when given the input via stdin is not a folder and iflag=directory is set.

[cre4ture]

hi @matrixhead . it seems that we are both working on dd right now. We need to sync to avoid double work. ^^
I'm usually announcing my work with a ticket. Especially when it's something larger.

[matrixhead]

@cre4ture sorry my bad i should've done that, i will try to do that from now on also since you were working on this issue could you give me your thoughts on this pr.

[cre4ture]

Don't worry. I'm working on dd, but I had luck that I skipped exactly this part that you where picking. So I don't expect I have much special thoughts in this PR other than other revievers. :-)

[github-actions]

GNU testsuite comparison:

Congrats! The gnu test tests/dd/misc is no longer failing!
Congrats! The gnu test tests/dd/not-rewound is no longer failing!
Congrats! The gnu test tests/timeout/timeout is no longer failing!

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/tail/inotify-dir-recreate (passes in this run but fails in the 'main' branch)

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/tail/inotify-dir-recreate (fails in this run but passes in the 'main' branch)

[github-actions]

GNU testsuite comparison:

Congrats! The gnu test tests/dd/misc is no longer failing!

[cakebaker]

Thanks for your PR and great to see that tests/dd/misc passes now :)