Missing handling of postgresql pgbackrest.conf template

pglift provides a template to configure pgbackrest, typically placed in ~/.config/pglift/pgbackrest/pgbackrest.conf and containing as default content :

[global]
lock-path = {lockpath}
log-path = {logpath}
spool-path = {spoolpath}

This is already handled by the pglift role, which writes the content of pglift_pgbackrest_conf_content to this file.

However, pglift also accepts a template at location ~/.config/pglift/postgresql/pgbackrest.conf, which defines some postgresql.conf parameters that are related to backups, with following default content :

wal_level = replica
archive_mode = on
archive_command = '{execpath} --config-path={configpath} --stanza={stanza} --pg1-path={datadir} archive-push %p'

But this template is currently not configurable via the pglift role. I suppose we need to define a new var pglift_postgresql_pgbackrest_conf_content to let users define it.