Fix test because we've got more authorities now

spec/authority_spec.rb

@@ -28,7 +28,7 @@ describe UKPlanningScraper::Authority do
     let(:all) { described_class.all }
     
     it 'returns all authorities' do
-      expect(all.count).to eq(48)
+      expect(all.count).to eq(56)
     end
     
     it 'returns a list of authorities' do