How to force sub-product-category to use the parent category template

I solved it, after facing these 2 issues:
1- use template_include in filter instead of taxonomy_template

2- I reordered these lines according to my need.

// Current first
$templates[] = "category-{$category->slug}.php";
$templates[] = "category-{$category->term_id}.php";

// Parent second
$templates[] = "category-{$parent->slug}.php";
$templates[] = "category-{$parent->term_id}.php";
$templates[] = 'category.php'; 

So here is my final code:

/**
* Filter the taxonomy hierarchy to inject a parent level of templates.
* 
* @param string $template The current template.
* @return string Filtered taxonomy template.
*/
function new_tax_hierarchy( $template ) {

    $term = get_queried_object();

    // If not an object, or the object doesn't have a taxonomy, bail.
    if ( ! is_object( $term ) || ! isset( $term->taxonomy ) )
        return $template;

    $taxonomy = $term->taxonomy;

    // If the taxonomy isn't hierarchical, bail.
    if ( ! is_taxonomy_hierarchical( $taxonomy ) )
        return $template;

    $templates = array();
    $parent_id = $term->parent;

    if ( 0 == $parent_id ) {
        // Use default values from get_taxonomy_template().
        $templates[] = "taxonomy-$taxonomy-{$term->slug}.php";
        $templates[] = "taxonomy-$taxonomy.php";
        $templates[] = 'taxonomy.php';
    } else {
        $parent = get_term( $parent_id, $taxonomy );

        // Parent templates.
        $templates[] = "taxonomy-$taxonomy-{$parent->slug}.php";
        $templates[] = "taxonomy-$taxonomy-{$parent->term_id}.php";
        $templates[] = 'taxonomy.php';

        // Current templates.
        $templates[] = "taxonomy-$taxonomy-{$term->slug}.php";
        $templates[] = "taxonomy-$taxonomy.php";
    }

    return locate_template( $templates );
}
add_filter( 'template_include', 'new_tax_hierarchy' );