better test name

spec/services/postcode_service_spec.rb

@@ -3,7 +3,7 @@ require "rails_helper"
 describe PostcodeService do
   let(:postcode) { "SR81LS\u00A0" }
 
-  it "triggers a validation error" do
+  it "returns clean postcode" do
     expect(described_class.clean(postcode)).to eq "SR81LS"
   end
 end