(FACT-3154) Updates socket parser error handling

Prior to this commit, the `mac_from` method would implicitly
return a logging object when rescuing an error when it should
return nil.

This commit updates the method to correctly return nil when
rescuing an error, which fixes some failing tests in Ruby >= 3.2.0.

Author: mhashizume

lib/facter/util/linux/socket_parser.rb

@@ -88,6 +88,7 @@ def mac_from(ifaddr)
             end
           rescue StandardError => e
             @log.debug("Could not read mac for interface #{ifaddr.name}, got #{e}")
+            nil
           end
 
           def mac_from_sockaddr_of(ifaddr)