nginx: move fastcgi cache to /var/lib/nginx

roles/archwiki/tasks/main.yml

@@ -30,6 +30,9 @@
   when: maintenance is not defined
   tags: ['nginx']
 
+- name: remove old fastcgi cache directory
+  file: path=/etc/nginx/wikicache state=absent
+
 - name: configure robots.txt
   copy: src=robots.txt dest="{{ archwiki_dir }}/robots.txt" owner=root group=root mode=0644
 

roles/archwiki/templates/nginx.d.conf.j2

-fastcgi_cache_path /etc/nginx/wikicache levels=1:2 keys_zone=wiki:100m inactive=60m;
+fastcgi_cache_path /var/lib/nginx/cache levels=1:2 keys_zone=wiki:100m inactive=60m;
 fastcgi_cache_key "$scheme$request_method$host$request_uri";
 
 upstream archwiki {