Updated dev-docker setup to not alter phpunit.xml

Tested on my machine via fresh dev instance with tests passing.
May need old users to drop their old volume data.

dev/docker/entrypoint.app.sh

@@ -10,7 +10,6 @@ else
     composer install
     wait-for-it db:3306 -t 45
     php artisan migrate --database=mysql
-    php artisan migrate --database=mysql_testing
     chown -R www-data:www-data storage
     exec apache2-foreground
 fi