chore: spoiler banner

package.json

@@ -1,6 +1,6 @@
 {
   "name": "coryd.dev",
-  "version": "20.8.0",
+  "version": "20.8.1",
   "description": "The source for my personal site. Built using 11ty (and other tools).",
   "type": "module",
   "scripts": {

src/pages/main/books/book.html

@@ -49,6 +49,7 @@ schema: book
     </div>
   </div>
   {% if book.review %}
+    {% render "partials/blocks/banners/warning.liquid", text: "There are probably spoilers after this banner — this is a warning about them." %}
     {{ book.review | markdown }}
     <hr />
   {% endif %}