fix(ip): Keep completing after -netns name

Author: yedayak

completions/ip

@@ -60,7 +60,7 @@ _comp_cmd_ip()
         [[ ${words[subcword]} == -b?(atch) ]] && return
         [[ $has_cmd ]] && subcmd=${words[subcword]} && break
         [[ ${words[subcword]} != -* &&
-            ${words[subcword - 1]} != -@(f?(amily)|rc?(vbuf)) ]] &&
+            ${words[subcword - 1]} != -@(f?(amily)|rc?(vbuf)|n?(etns)) ]] &&
             cmd=${words[subcword]} has_cmd=set
     done