CODE EXAMPLE FOR PHP

change logo url on wordpress website

function oceanwp_child_modify_logo_link( $html, $blog_id ) {
  $custom_logo_id = get_theme_mod( 'custom_logo' );
  $html = sprintf(
    '<a href="%1$s" class="custom-logo-link" rel="home">%2$s</a>',
    esc_url( 'https://google.com/' ), 
    wp_get_attachment_image( $custom_logo_id, 'full', false, $custom_logo_attr )
  );

  return $html;
}

add_filter( 'get_custom_logo', 'oceanwp_child_modify_logo_link', 10, 2 );