Fixed call to member function is_visible Fatal Error (#51286)

* Fixed call to member function is_visible Fatal Error

* Implemented the suggestions

* Add changefile(s) from automation for the following project(s): woocommerce

* Updated the @version tag

* Promote 'comment' to actual changelog entry.

* Add changefile(s) from automation for the following project(s): woocommerce

---------

Co-authored-by: github-actions <github-actions@github.com>
Co-authored-by: Barry Hughes <3594411+barryhughes@users.noreply.github.com>

plugins/woocommerce/changelog/51286-51176-fixed-fatal-is_visible-func

@@ -0,0 +1,4 @@
+Significance: patch
+Type: fix
+Comment: Fixed call to a member function is_visible() on string | content-product.php:23
+

plugins/woocommerce/templates/content-product.php

@@ -12,15 +12,15 @@
  *
  * @see     https://woocommerce.com/document/template-structure/
  * @package WooCommerce\Templates
- * @version 3.6.0
+ * @version 9.4.0
  */
 
 defined( 'ABSPATH' ) || exit;
 
 global $product;
 
-// Ensure visibility.
-if ( empty( $product ) || ! $product->is_visible() ) {
+// Check if the product is a valid WooCommerce product and ensure its visibility before proceeding.
+if ( ! is_a( $product, WC_Product::class ) || ! $product->is_visible() ) {
 	return;
 }
 ?>