Update vendor dependencies
Summary:
Update to wikimedia/slimapp v0.9.0 and phpmailer/phpmailer v6.0.6.
$ composer update --no-dev Loading composer repositories with package information Updating dependencies Package operations: 1 install, 4 updates, 0 removals - Updating psr/log (1.0.2 => 1.1.0): Loading from cache - Installing symfony/polyfill-ctype (v1.10.0): Loading from cache - Updating twig/twig (v1.35.0 => v1.35.4): Loading from cache - Updating phpmailer/phpmailer (v5.2.9 => v6.0.6): Loading from cache - Updating wikimedia/slimapp (v0.8.0 => v0.9.0): Loading from cache Writing lock file Generating autoload files
Bug: T207222
Reviewers: Niharika, Bawolff
Reviewed By: Niharika
Maniphest Tasks: T207222
Differential Revision: https://phabricator.wikimedia.org/D1128