Apply suggestion about setting keepSuffixPattern

Co-authored-by: Kilian Schulte <[email protected]>

Author: parlough

site/lib/main.dart

@@ -33,7 +33,10 @@ void main() {
 Component get _docsFlutterDevSite => ContentApp.custom(
   eagerlyLoadAllPages: true,
   loaders: [
-    FilesystemLoader(path.join(siteSrcDirectoryPath, 'content')),
+    FilesystemLoader(
+      path.join(siteSrcDirectoryPath, 'content'),
+      keepSuffixPattern: RegExp(r'.*\.(txt|json|pdf)$'),
+    ),
     MemoryLoader(pages: allMemoryPages),
   ],
   configResolver: PageConfig.all(