fix(): exclude custom subsections (#7298)

Author: mhartington

content/200-orm/500-reference/300-errors/_category_.json

@@ -1,3 +1,5 @@
 {
-  "className": "hidden-sidebar"
+  "className": "hidden-sidebar",
+  
+  "customProps": { "hide_from_subsection": true }
 }

src/theme/DocCardList/index.tsx

@@ -19,7 +19,11 @@ export default function DocCardList(props: Props): JSX.Element {
   }
   const [filteredItems, setFilteredItems] = useState<any>(filterDocCardListItems(items));
   useEffect(() => {
-    setFilteredItems(filteredItems.filter((e: any) => e?.href?.slice(0, -1) !== location.pathname));
+    setFilteredItems(prevFilteredItems => 
+      prevFilteredItems
+        .filter((e: any) => e?.href?.slice(0, -1) !== location.pathname)
+        .filter((e: any) => !e?.customProps?.hide_from_subsection)
+    );
   }, [items]);
   return (
     <section className={clsx("row", className)}>