Hello Fatih,

This is a readme file where everything is explained, and the mentioned function is used for testing purposes so in this file there is only an explanation of the function - how you can use it to test. The function itself is used for testing some vulnerabilities and that is probably why the security plugin is alerting you about presence of this function somewhere. But in the readme file it is only a explanation of how to use it, so you don't need to worry about this and do nothing about this accordingly. 

Also, this file is a part of a library which is used in Amelia and many other software use it out there. So, this will not cause any issue on your website or any security troubles, no worries. You don't need to change/do anything about this. 

If you have any further questions or concerns feel free to ask,