Apply database updates...
Fatal error: Uncaught Error: Call to undefined function passthru() in /home/yukonw3creatives/public_html/vendor/evolvingweb/drupal-ci/pantheon/quicksilver/drush_update_db.php:5
Stack trace:
#0 {main}
thrown in /home/yukonw3creatives/public_html/vendor/evolvingweb/drupal-ci/pantheon/quicksilver/drush_update_db.php on line 5