Enabling PHP 7.1.4 on import turns on debug in some unknown way

I imported a Flywheel backup using the preferred configuration. it worked just fine.

I deleted it and reimported it using a custom configuration, specifying PHP 7.1.4 and MySQL 5.6. When I view the site, debug appears to be turned on and I am getting errors displayed that normally are suppressed with debug off.

I looked at both wp_config.php and php.ini. wp_config had nothing enabed. php.ini had a section about Xdebug that looked like some kind of debugging might be enabled.

Any idea why I get different behavior between PHP 5.6 and 7.1 for debug? How can I turn this back off?