postfix: Install PCRE explicit after package split[1]

[1] https://lists.archlinux.org/pipermail/arch-dev-public/2021-January/030284.html

roles/postfix/tasks/main.yml

 ---
 
 - name: install postfix
-  pacman: name=postfix state=present
+  pacman: name=postfix,postfix-pcre state=present
 
 - name: install template configs
   template: src={{ item }}.j2 dest=/etc/postfix/{{ item }} owner=root group=root mode=0644