Refactor uploads preview error banner to use a shared component

Also refactor a corresponding test to avoid asserting on the content

app/templates/partials/check/letter-validation-failed-banner.html

@@ -2,9 +2,13 @@
 
 {% call banner_wrapper(type='dangerous') %}
   {% if message is string %}
-    <h1 class="banner-title">{{ message }}</h1>
+    <h1 class="banner-title">
+      {{ message }}
+    </h1>
   {% else %}
-    <h1 class="banner-title">{{ message.title }}</h1>
+    <h1 class="banner-title" data-module="track-error" data-error-type="{{ error_code }}" data-error-label="precompiled letter validation failed for service_id: {{ current_service.id }}">
+      {{ message.title }}
+    </h1>
     {% if message.detail %}
       <p>
         {{ message.detail | safe }}