Dont fail_with on check

Author: jvazquez-r7

modules/exploits/windows/local/ms_ndproxy.rb

@@ -294,7 +294,7 @@ def check
 
     handle = open_device("\\\\.\\NDProxy")
     if handle.nil?
-      fail_with(Failure::NoTarget, "\\\\.\\NDProxy device not found")
+      return Exploit::CheckCode::Safe
     end
     session.railgun.kernel32.CloseHandle(handle)