Add PSR-3-compatible logger and pass in to MediaWiki\OAuthClient\Client #1050
Description
Add a PSR-3-compatible logging library, such as monolog, to ACC and pass it in to the instantiation of the MediaWiki\OAuthClient\Client library so that we have access to diagnostic information, which would have been very helpful for figuring out the JWT/OAuth issues we've recently been having, which turned out to be caused by clock drift on the application server. It would also probably be helpful to start adding internal logging statements in the codebase itself to assist in debugging in general.
As part of this, we'll need to decide where the log messages should be written to, how to manage log rotation and retention, etc.