fix(perl): helper call regression from 01611dd

#965 (comment)

Thanks-to: Koichi Murase <myoga.murase@gmail.com>

completions/perl

@@ -5,7 +5,7 @@ _comp_cmd_perl__helper()
     COMPREPLY=($(compgen -P "$prefix" -W \
         "$("${1:-perl}" "${BASH_SOURCE[0]%/*}/../helpers/perl" "$2" "$cur")" \
         -- "$cur"))
-    [[ $1 == functions ]] || _comp_ltrim_colon_completions "$prefix$cur"
+    [[ $2 == functions ]] || _comp_ltrim_colon_completions "$prefix$cur"
 }
 
 _comp_cmd_perl()