Fix variable name

Author: samdoiron

filters/where.md

@@ -15,7 +15,7 @@ All products:
 - {{ product.title }}
 {% endfor %} 
 
-{% assign kitchen_products = site.pages | where: "type", "kitchen" %}
+{% assign kitchen_products = products | where: "type", "kitchen" %}
 
 Kitchen products:
 {% for product in kitchen_products %}
@@ -87,4 +87,4 @@ Featured product: {{ new_shirt.title }}
 <p class="code-label">Output</p>
 ```text
 Featured product: Hawaiian print sweater vest
-```
+```