Revert "Use Monolog provider for beta logging"

This reverts commit e642f5fe31496903dd9cfe8c62ad7599a225481c.

PHP Fatal error:  Call to undefined method MWLoggerLegacyLogger::setFormatter() in /mnt/srv/mediawiki-staging/php-master/includes/debug/logger/monolog/Spi.php on line 222

Change-Id: I97c24085e8da08841ce4ee3fad2def27304e0cba