cli: hide certificate blobs unless --show-secrets is passed

This restores the behavior before commit 99711579.

Fixes: 99711579 ('cli: add property type for 802-1x certificate properties (pt2)').
12 jobs for bg/rh1702199 in 89 minutes and 52 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Test
passed #267267
allowed to fail
checkpatch

00:03:27

passed #267274
t_debian:9

00:11:28

passed #267276
t_debian:sid

00:13:34

manual #267275
allowed to fail manual
t_debian:testing
failed #267268
t_fedora:28

01:29:51

passed #267269
t_fedora:29

00:25:53

failed #267270
t_fedora:30

01:29:51

manual #267271
allowed to fail manual
t_fedora:rawhide
passed #267272
t_ubuntu:16.04

00:13:33

passed #267273
t_ubuntu:18.04

00:13:43

 
  External
failed NetworkManager test verification

failed NetworkManager test verification

05:56:05

 
Name Stage Failure
failed
t_fedora:30 Test There has been a timeout failure or the job got stuck. Check your timeout limits or try again
Copying file po/Rules-quot
Copying file po/boldquot.sed
Copying file po/en@boldquot.header
Copying file po/en@quot.header
Copying file po/insert-header.sin
Copying file po/quot.sed
Copying file po/remove-potcdate.sin
autoreconf: Entering directory `.'
autoreconf: running: intltoolize --automake --copy --force
autoreconf: running: aclocal --force
failed
t_fedora:28 Test There has been a timeout failure or the job got stuck. Check your timeout limits or try again
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