How can I whitelist a URL via .htaccess?

If you go to http://www.t****rs.org and click on the profile icon you will get a login form - Try and login with any of the social media icons - it gives the following error:

“Forbidden: You don't have permission to access /wp-content/plugins/wordpress-social-login/hybridauth/ on this server.”

When I troubleshooted the Wordpress Social Login plugin the following is said:
404, or 403 HTTP Error.
This issue usually happen when :
There is a .htaccess file who prevent direct access to the WordPress plugins directory.
Your web host uses mod_security to block requests containing URLs (eg. hosts like HostGator, GoDaddy and The Planet).
In any of these two cases, WSL requires this url to be white-listed:
wp-content/plugins/wordpress-social-login/hybridauth/

As suggested during the chat, I tried to place a .htaccess file in that directory (/wp-content/plugins/wordpress-social-login/hybridauth/) with the following rule (for Apache 2.4 and above):

<Files *.php>
Require all granted
</Files>

But I’m still getting the same error. Is there any other way to whitelist a URL via .htaccess or another way to achieve this?

Thank you very much for your help.