MyTravel - Rename filter dropdown option name

functions.php

$instance = MAS_Travels::instance();

remove_filter( 'woocommerce_dropdown_variation_attribute_options_html', array( $instance, 'mas_travels_filter_dropdown_option_html' ), 12, 2 );

add_filter( 'woocommerce_dropdown_variation_attribute_options_html','mas_travels_filter_dropdown_option_html',12, 2  );

function mas_travels_filter_dropdown_option_html( $html, $args ) {
    global $product;
    $product_format = get_product_format() ? get_product_format() : 'standard';
    $product_type   = $product->get_type();

    if ( 'tour' === $product_format || 'activity' === $product_format ) :
        $show_option_none_text = $args['show_option_none'] ? $args['show_option_none'] : esc_html__( 'Select', 'mas-travels' );
        $show_option_none_html = '<option value="">' . esc_html( $show_option_none_text ) . '</option>';

        $html = str_replace( $show_option_none_html, '<option value="">' . esc_html( 'Select' ) . '</option>', $html );

    endif;
    return $html;
}