Update simple_backdoors_exec.rb

Author: shipcod3

modules/exploits/multi/http/simple_backdoors_exec.rb

@@ -82,8 +82,6 @@ def http_send_command(cmd)
     })
     if !res && res.code == 200
       fail_with(Failure::Unknown, "Failed to execute the command.")
-    else
-      fail_with(Failure::Unknown, "#{res.code} #{res.message}")
     end
   end