Remove erroneous newline

Author: wvu

lib/msf/ui/console/command_dispatcher/core.rb

@@ -529,7 +529,6 @@ def cmd_history_help
     print_line
     print_line "Shows the command history."
     print_line "If -n is not set, only the last #{@history_limit} commands will be shown."
-    print_line
     print @@history_opts.usage
   end