stack/slapos: Version up psutil 5.6.3

It is proven to work on Debian 10.

/reviewed-on !640
10 jobs for cmf_upgrade_versions in 0 seconds (queued for 1 second)
Status Job ID Name Coverage
  External
failed SLAPOS-SR-TEST-MASTER

04:31:23

failed SLAPOS-SR-TEST-MASTER

05:25:23

failed SLAPOS-SR-TEST-MASTER

04:27:52

failed SLAPOS-SR-TEST-MASTER

04:28:32

failed SLAPOS-SR-TEST-MASTER

04:51:02

failed SLAPOS-SR-TEST-MASTER

04:22:28

failed SLAPOS-SR-TEST-MASTER

02:13:26

failed SLAPOS-SR-TEST-MASTER

03:23:17

failed SLAPOS-SR-TEST-MASTER

04:47:24

failed SLAPOS-SR-TEST-MASTER

04:58:52