Pass the data_directory to the postgresql_server_conf resource

Previously we were passing it as an additional config, but it is set by
default. The last value was used, the custom one, so the server still
used the correct file

site-cookbooks/kosmos-postgresql/resources/server.rb

@@ -64,8 +64,7 @@ action :create do
     unix_socket_directories: "/var/run/postgresql",
     dynamic_shared_memory_type: "posix",
     timezone: "UTC", # default is GMT
-    listen_addresses: "0.0.0.0",
-    data_directory: postgresql_data_dir
+    listen_addresses: "0.0.0.0"
   }
 
   if new_resource.role == "replica"
@@ -101,6 +100,7 @@ action :create do
 
   postgresql_server_conf "main" do
     version postgresql_version
+    data_directory postgresql_data_dir
     additional_config additional_config
     notifies :reload, "service[#{postgresql_service}]", :delayed
   end