Fix flaky merged schemes test

spec/services/merge/merge_organisations_service_spec.rb

@@ -1317,9 +1317,9 @@ RSpec.describe Merge::MergeOrganisationsService do
           merging_organisation.reload
           expect(new_absorbing_organisation.owned_lettings_logs.count).to eq(2)
           expect(new_absorbing_organisation.managed_lettings_logs.count).to eq(1)
-          expect(new_absorbing_organisation.owned_lettings_logs.find(owned_lettings_log.id).scheme).to eq(new_absorbing_organisation.owned_schemes.first)
-          expect(new_absorbing_organisation.owned_lettings_logs.find(owned_lettings_log.id).location).to eq(new_absorbing_organisation.owned_schemes.first.locations.first)
-          expect(new_absorbing_organisation.owned_lettings_logs.find(owned_lettings_log_no_location.id).scheme).to eq(new_absorbing_organisation.owned_schemes.first)
+          expect(new_absorbing_organisation.owned_lettings_logs.find(owned_lettings_log.id).scheme).to eq(new_absorbing_organisation.owned_schemes.find_by(service_name: scheme.service_name))
+          expect(new_absorbing_organisation.owned_lettings_logs.find(owned_lettings_log.id).location).to eq(new_absorbing_organisation.owned_schemes.find_by(service_name: scheme.service_name).locations.first)
+          expect(new_absorbing_organisation.owned_lettings_logs.find(owned_lettings_log_no_location.id).scheme).to eq(new_absorbing_organisation.owned_schemes.find_by(service_name: scheme.service_name))
           expect(new_absorbing_organisation.owned_lettings_logs.find(owned_lettings_log_no_location.id).location).to eq(nil)
         end