Description of problem:
During the satellite-installer configuration, if you try to set an invalid IP address, it's accepting and breaking the configuration.

Version-Release number of selected component (if applicable):
6.15

How reproducible:
100%

Actual results:
1 error was detected during installation.
Please address the errors and re-run the installer to ensure the system is properly configured.
Failing to do so is likely to result in broken functionality.

The full log is at /var/log/foreman-installer/satellite.log

Expected results:
... [NOTICE] [configure] System configuration has finished.
  Success!

Additional info:
If was performed the command like the example below it breaks the configuration:
~~~
satellite-installer --foreman-proxy-dns-forwarders ""
~~~

Looking at the yaml file, we see the data below:
~~~ command: grep -A1 forward /etc/foreman-installer/scenarios.d/satellite-answers.yaml
 dns_forwarders:
 - ''
~~~

The workaround:
~~~
satellite-installer --reset-foreman-proxy-dns-forwarders
~~~

After that, we see a valid data:
~~~ command:  grep -A1 forward /etc/foreman-installer/scenarios.d/satellite-answers.yaml 
  dns_forwarders: []
  libvirt_network: default
~~~