Sanitise existing HTML in Enterprise#long_description

We will add a migration to sanitise all existing descriptions but before
we do that destructive action, it's good to test this in a read-only
fashion first.

app/models/enterprise.rb

@@ -247,6 +247,11 @@ class Enterprise < ApplicationRecord
     count(distinct: true)
   end
 
+  # Remove any unsupported HTML.
+  def long_description
+    HtmlSanitizer.sanitize(super)
+  end
+
   # Remove any unsupported HTML.
   def long_description=(html)
     super(HtmlSanitizer.sanitize(html))

spec/models/enterprise_spec.rb

@@ -403,6 +403,11 @@ RSpec.describe Enterprise do
       subject.long_description = "Hello <script>alert</script> dearest <b>monster</b>."
       expect(subject.long_description).to eq "Hello alert dearest <b>monster</b>."
     end
+
+    it "sanitises existing HTML in long_description" do
+      subject[:long_description] = "Hello <script>alert</script> dearest <b>monster</b>."
+      expect(subject.long_description).to eq "Hello alert dearest <b>monster</b>."
+    end
   end
 
   describe "callbacks" do