Where is httpd.conf file of a domain? (Plesk, Apache, CentOS, Dedicated Server.)
Try
locate httpd.conf on the commend line.Note that in newer Apache setups, the configuration is spread across multiple files, but they won't be far from where you find httpd.conf.
I had the same problem, but reading @user1055645 comment in the question, about follow the file:
/etc/httpd/conf.d/zz010_psa_httpd.conf
I found the configuration file here:
/etc/httpd/conf/plesk.conf.d/vhosts/domain.com.conf
If you want to disable access_log you can edit this file and comment with an # the beginning of this line:
CustomLog /var/www/vhosts/system/giornalone.it/logs/access_log plesklog
At the end restart apache server to make the changes take effect.