Remove aria-labelledby and associated id on h2 in error summary

In JAWS 2022, the screen reader is focusing on the error summary on load and only reading out the title because of this aria-labelledby. By removing it, we make it possible to access the content inside the error summary, communicating to screen readers why there is a problem.

src/govuk/components/error-summary/template.njk

@@ -1,11 +1,11 @@
 <div class="govuk-error-summary
-  {%- if params.classes %} {{ params.classes }}{% endif %}" aria-labelledby="error-summary-title"
+  {%- if params.classes %} {{ params.classes }}{% endif %}"
   {%- if params.disableAutoFocus %} data-disable-auto-focus="true"{% endif %}
   {%- for attribute, value in params.attributes %} {{ attribute }}="{{ value }}"{% endfor %} data-module="govuk-error-summary">
   {# Keep the role="alert" in a seperate child container to prevent a race condition between
   the focusing js at the alert, resulting in information getting missed in screen reader announcements #}
   <div role="alert">
-    <h2 class="govuk-error-summary__title" id="error-summary-title">
+    <h2 class="govuk-error-summary__title">
       {{ params.titleHtml | safe if params.titleHtml else params.titleText }}
     </h2>
     <div class="govuk-error-summary__body">

src/govuk/components/error-summary/template.test.js

@@ -18,13 +18,6 @@ describe('Error-summary', () => {
       expect(results).toHaveNoViolations()
     })
 
-    it('aria-labelledby attribute matches the title id', () => {
-      const $ = render('error-summary', examples.default)
-      const ariaAttr = $('.govuk-error-summary').attr('aria-labelledby')
-
-      expect(ariaAttr).toEqual('error-summary-title')
-    })
-
     it('has a child container with the role=alert attribute', () => {
       const $ = render('error-summary', examples.default)
       const childRoleAttr = $('.govuk-error-summary div:first-child').attr('role')