CLDC-1841 Copy change for net income known question (#1386)

* copy change for net income known question

* add minimal testing for question

app/models/form/lettings/questions/net_income_known.rb

@@ -2,7 +2,7 @@ class Form::Lettings::Questions::NetIncomeKnown < ::Form::Question
   def initialize(id, hsh, page)
     super
     @id = "net_income_known"
-    @check_answer_label = "Do you know the household’s combined income?"
+    @check_answer_label = "Do you know the household’s combined total income after tax?"
     @header = "Do you know the household’s combined income after tax?"
     @type = "radio"
     @check_answers_card_number = 0

spec/models/form/lettings/questions/net_income_known_spec.rb

@@ -0,0 +1,17 @@
+require "rails_helper"
+
+RSpec.describe Form::Lettings::Questions::NetIncomeKnown do
+  subject(:question) { described_class.new(nil, {}, nil) }
+
+  describe "#id" do
+    it "is net_income_known" do
+      expect(question.id).to eql("net_income_known")
+    end
+  end
+
+  describe "#type" do
+    it "is radio" do
+      expect(question.type).to eql("radio")
+    end
+  end
+end