Fix Single Product Classic Template block not showing on the front-end (

#11455)

In WordPress 6.4, it appears that the global `have_posts` is `false` in
the context of the full site editing single product template. This
breaks the Classic Template block.

In this commit, we are creating a custom query using the available id
instead of relying on the global query.

This might be a temporary workaround as we are waiting to see
if that's an issue that core is willing to fix, as it might affect
backwards-compatibility for other vendors.

src/BlockTypes/ClassicTemplate.php

@@ -173,9 +173,16 @@ protected function render_single_product() {
 		 */
 		do_action( 'woocommerce_before_main_content' );
 
-		while ( have_posts() ) :
+		$product_query = new \WP_Query(
+			array(
+				'post_type' => 'product',
+				'p'         => get_the_ID(),
+			)
+		);
+
+		while ( $product_query->have_posts() ) :
 
-			the_post();
+			$product_query->the_post();
 			wc_get_template_part( 'content', 'single-product' );
 
 		endwhile;