Do not error if owning_organisation is nil

app/services/exports/lettings_log_export_service.rb

@@ -266,7 +266,7 @@ module Exports
             form << doc.create_element(key, value)
           end
         end
-        form << doc.create_element("providertype", lettings_log.owning_organisation.read_attribute_before_type_cast(:provider_type))
+        form << doc.create_element("providertype", lettings_log.owning_organisation&.read_attribute_before_type_cast(:provider_type))
       end
 
       xml_doc_to_temp_file(doc)

spec/services/exports/lettings_log_export_service_spec.rb

@@ -128,7 +128,7 @@ RSpec.describe Exports::LettingsLogExportService do
     context "and multiple lettings logs are available for export on same quarter" do
       before do
         FactoryBot.create(:lettings_log, startdate: Time.zone.local(2022, 2, 1), needstype: 2)
-        FactoryBot.create(:lettings_log, startdate: Time.zone.local(2022, 3, 20))
+        FactoryBot.create(:lettings_log, startdate: Time.zone.local(2022, 3, 20), owning_organisation: nil)
       end
 
       it "generates an XML manifest file with the expected content within the ZIP file" do