/* change login link to go custom link and not to /my-account/ */

function my_woocommerce_notice_link( $message ) {

  if ( strpos( $message, 'Sorry, you must be logged in to place a bid. <a href="https://your-webpage.com/my-account/" class="button">Login &rarr;</a>' ) !== false ) {
    $message = 'Sorry, you must be logged in to place a bid. <a href="https://your-webpage.com/login/" class="button">Login &rarr;</a>';
  }
  return $message;
}
add_filter( 'woocommerce_add_error', 'my_woocommerce_notice_link' );