sip: Do not fail if CallsNetworkWatch is unavailable

In this case network changes will not be detected.
Additionally fall back to binding on all network interfaces (in this case a user
will have problems when using multiple network interfaces, but there is really
not much we can do without a functioning CallsNetworkWatch).
8 jobs for master in 28 minutes and 27 seconds (queued for 5 seconds)
Status Name Job ID Coverage
  Build
passed build:native #1538834

00:03:05

 
  Test
passed build-gtkdoc #1538836

00:02:39

passed check-po #1538837

00:00:50

passed test:native #1538835

00:02:52

21.6%
passed validate-metadata #1538838

00:00:47

 
  Package
passed flatpak:master #1538841
flatpak

00:22:29

passed package-debian-bookworm #1538839

00:04:28

passed package-deb-pureos-byzantium:arm64 #1538840
aarch64

00:07:29