Fix postgres installation

Also, do not start at boot anymore, in favor of path-based activation.

site-cookbooks/kosmos-postgresql/recipes/default.rb

@@ -27,13 +27,13 @@
 postgresql_version = "12"
 postgresql_service = "postgresql@#{postgresql_version}-main"
 
-postgresql_custom_server postgresql_version do
-  role "primary"
+# TODO check if still necessary
+user "postgres" do
+  manage_home false
 end
 
-service postgresql_service do
-  supports restart: true, status: true, reload: true
-  action [:enable]
+postgresql_custom_server postgresql_version do
+  role "primary"
 end
 
 # This will only be run once, if the /var/lib/postgresql/10/main directory