feat(single.html): Add provider and comments info for non-production (#5068)

_layouts/single.html

@@ -65,8 +65,15 @@ layout: default
       {% include post_pagination.html %}
     </div>
 
-    {% if jekyll.environment == 'production' and site.comments.provider and page.comments %}
+    {% if site.comments.provider and page.comments %}
-      {% include comments.html %}
+      {% if jekyll.environment == 'production' %}
+        {% include comments.html %}
+      {% else %}
+        <p>
+          Comments are configured with provider: <strong>{{ site.comments.provider }}</strong>,
+          but are disabled in non-production environments.
+        </p>
+      {% endif %}
     {% endif %}
   </article>