If you are not actually using Bootstrap on your site you can disable it at Toolset > Settings, but if you need it elsewhere you can dequeue Bootstrap on just the checkout page by adding a PHP snippet, at Toolset > Settings > Custom Code:
/**
* Don't enqueue Bootstrap on WC Products archive
*/
function dequeue_bootstrap(){
if ( is_page( 'checkout' ) ) { // edit if checkout page slug is different
// dequeue Bootstrap CSS
function dequeue_bootstrap_css(){
wp_dequeue_style( 'toolset_bootstrap_styles' );
wp_dequeue_style( 'toolset_bootstrap_4' );
}
add_action( 'wp_print_styles', 'dequeue_bootstrap_css' );
// dequeue Bootstrap JS
function dequeue_bootstrap_js(){
wp_dequeue_script( 'toolset_bootstrap' );
wp_dequeue_script( 'toolset_bootstrap_4' );
}
add_action( 'wp_print_scripts', 'dequeue_bootstrap_js' );
}
}
add_action( 'wp_enqueue_scripts', 'dequeue_bootstrap', 100 );