cli: don't wait for connection change on update failure

When saving a connection, we wait the connection-changed signal before
proceeding to ensure that the remote connection is up to date.
However, no signal is emitted if the update fails and so we shouldn't
wait for it.

Fixes: a370faeb ('cli: wait for changed signal after updating a connection'):

https://bugzilla.redhat.com/show_bug.cgi?id=1702203
12 jobs for bg/rh1702203 in 46 minutes and 13 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Test
passed #258054
allowed to fail
checkpatch

00:00:57

passed #258061
t_debian:9

00:22:27

passed #258063
t_debian:sid

00:11:46

manual #258062
allowed to fail manual
t_debian:testing
passed #258055
t_fedora:28

00:29:14

passed #258056
t_fedora:29

00:46:12

failed #258057
t_fedora:30

00:00:22

manual #258058
allowed to fail manual
t_fedora:rawhide
passed #258059
t_ubuntu:16.04

00:14:48

passed #258060
t_ubuntu:18.04

00:22:38

 
  External
failed NetworkManager test verification

failed NetworkManager test verification

06:00:44

 
Name Stage Failure
failed
t_fedora:30 Test
$ date '+%Y%m%d-%H%M%S'; NM_INSTALL="dnf install -y" ./contrib/fedora/REQUIRED_PACKAGES
20190423-203242
Fedora Modular 30 - x86_64 3.4 MB/s | 2.1 MB 00:00
Fedora Modular 30 - x86_64 - Updates 459 B/s | 257 B 00:00
Fedora Modular 30 - x86_64 - Test Updates 4.4 MB/s | 2.9 MB 00:00
Fedora 30 - x86_64 - Test Updates 14 MB/s | 16 MB 00:01
Fedora 30 - x86_64 - Updates 455 B/s | 257 B 00:00
./contrib/fedora/REQUIRED_PACKAGES: line 13: 11 Segmentation fault (core dumped) $NM_INSTALL "$@"
ERROR: Job failed: exit code 1