Increase zram-fraction to 1.0 for lists.archlinux.org

It's been running out of swap during borg-backup and seems to get good
compression ratios; try upping the zram size to 100% of RAM (from 50%).

host_vars/lists.archlinux.org/misc

 ---
 filesystem: btrfs
 ipv4_address: 95.217.236.249
+zram_fraction: 1.0
 wireguard_address: 10.0.0.34
 wireguard_public_key: t6Er4qAMe/lWNnAByWdXhbUwXKYfj9CkkJgMp28UQl8=

roles/common/files/zram-generator.conf

-[zram0]
-max-zram-size = none

roles/common/tasks/main.yml

@@ -139,7 +139,7 @@
   when: enable_zram_swap
 
 - name: install zram-generator config for zram
-  copy: src=zram-generator.conf dest=/etc/systemd/zram-generator.conf owner=root group=root mode=0644
+  template: src=zram-generator.conf dest=/etc/systemd/zram-generator.conf owner=root group=root mode=0644
   notify:
     - restart systemd-zram-setup@zram0
   when: enable_zram_swap

roles/common/templates/zram-generator.conf

+[zram0]
+max-zram-size = none
+{% if zram_fraction is defined %}
+zram-fraction = {{ zram_fraction }}
+{% endif %}