common: Update package cache in case the pacman.conf is changed

roles/common/handlers/main.yml

@@ -14,3 +14,6 @@
 
 - name: restart systemd-swap
   service: name=systemd-swap state=restarted
+
+- name: update package cache
+  pacman: update_cache=yes

roles/common/tasks/main.yml

@@ -143,6 +143,8 @@
 
 - name: install pacman config
   template: src=pacman.conf.j2 dest=/etc/pacman.conf mode=0644 owner=root group=root
+  notify:
+    - update package cache
 
 - name: install custom paccache.service
   copy: src=paccache.service dest=/etc/systemd/system/paccache.service owner=root group=root mode=0644