feat: add user certificate to Certificate render start context

Add the user certificate to the CertificateRenderStarted Open edX filter context, so it is possible to have complex filtering and applying
custom logic to the course certificate presentation.

fccn/nau-technical#667

Author: igobranco

lms/djangoapps/certificates/views/webview.py

@@ -585,6 +585,21 @@ def render_html_view(request, course_id, certificate=None):  # pylint: disable=t
         context.update(get_certificate_header_context(is_secure=request.is_secure()))
         context.update(get_certificate_footer_context())
 
+        # Append/Override the existing view context values with plugin defined values
+        run_extension_point(
+            'NAU_CERTIFICATE_CONTEXT_EXTENSION',
+            context=context,
+            request=request,
+            course=course,
+            user=user,
+            user_certificate=user_certificate,
+            configuration=configuration,
+            certificate_language=certificate_language,
+        )
+
+        # NAU Customization so the filter know which certificate is being rendered
+        context['user_certificate'] = user_certificate
+
         # Append/Override the existing view context values with any course-specific static values from Advanced Settings
         context.update(course.cert_html_view_overrides)