Add default for LARAVEL_BLOCKER_DATABASE_CONNECTION env variable

Author: blinkofaneye

.env.example

@@ -114,6 +114,7 @@ LARAVEL_LOGGER_FONT_AWESOME_CDN_URL=https://maxcdn.bootstrapcdn.com/font-awesome
 LARAVEL_LOGGER_BOOTSTRAP_CSS_CDN_ENABLED=false
 LARAVEL_LOGGER_BOOTSTRAP_CSS_CDN_URL=https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css
 
+LARAVEL_BLOCKER_DATABASE_CONNECTION=mysql
 LARAVEL_BLOCKER_USER_MODEL=App\Models\User
 LARAVEL_BLOCKER_AUTH_ENABLED=true
 LARAVEL_BLOCKER_ROLES_ENABLED=true