psmisc: upgrade 23.5 -> 23.6

Changelog:
=========
* buildsys: Fix DEJAGNU work-around Debian #1015089
* killall: Use kill if pidfd_send_signal fails Debian #1015228
* fuser: Do not mention nonexistent - reset option #42
* fuser: Use modern statn where possible
* pstree: Better AppArmor support !30

Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>