[DOCS] network_settings beacon doesn't list dependency. 

**Description**
https://docs.saltproject.io/en/latest/ref/beacons/all/salt.beacons.network_settings.html does not list proute2 as a dependency even though it is a dependency.

**Suggested Fix**
list dependency 

**Type of documentation**
salt beacons

**Location or format of documentation**
https://docs.saltproject.io/en/latest/ref/beacons/all/salt.beacons.network_settings.html
