Add php-fpm user and group for log file ownership

This commit introduces the php-fpm user and group, assigning ownership of relevant log files to ensure proper permissions. Updates were also made to the logrotate configuration to include the `su` directive for php-fpm. These changes improve compatibility and address log management requirements.

templates/logrotate/chill

@@ -1,4 +1,5 @@
 /var/log/chill/default-*.log {
+  su php-fpm php-fpm
   rotate 90
   daily
   compress
@@ -7,6 +8,7 @@
 }
 
 /var/log/apt/private-*.log {
+  su php-fpm php-fpm
   rotate 180
   daily
   compress