fix: less opinionated pds operator hostname

vars/main.yml.example

@@ -55,3 +55,4 @@ pds_crawlers: https://relay.fire.hose.cam  # relay/crawler endpoint
 pds_operator_enabled: true
 pds_operator_repo: https://tangled.org/brookie.blog/pds-operator
 pds_operator_version: main
+pds_operator_hostname: pds-operator.cosocial.ca