gunicorn: disable sentry logging event reporting by default
By default, sentry's logging integration will report any error or exception-level logging as an event.
Now that we explicitly capture exceptions in the RPC server app, we can disable this automatic event generation, and only use the logging integration to generate breadcrumbs.
Test Plan
updated the gunicorn config tests to check that the logging integration is properly overridden
Migrated from D7567 (view on Phabricator)