fix: update body copy and make page title renders correctly

app/views/school/register_ect/start.html.erb

@@ -1,12 +1,12 @@
-<% page_data(title: "What you'll need", error: false) %>
+<% page_data(title: sanitize("What you'll need"), error: false) %>
 
 <h2 class="govuk-heading-m">Personal information</h2>
 <p class="govuk-body">You must provide your ECT's:</p>
 <ul class="govuk-list govuk-list--bullet">
   <li>name</li>
   <li>date of birth</li>
   <li>email address</li>
-  <li>teaching reference number (TRN)</li>
+  <li>teacher reference number (TRN)</li>
 </ul>
 
 <h2 class="govuk-heading-m">Training details</h2>