Add patch to remove conduit_connectionlog table (Fixes T9982)

Summary: Adds a schema patch that removes conduit_connectionlog. This table hasn't been used in 8ish months so it's probably safe to get rid of.

Test Plan: Apply the patch locally and confirm that the table does indeed get dropped.

Reviewers: Blessed Reviewers, epriestley

Reviewed By: Blessed Reviewers, epriestley

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D16438