add_remove_shards_killop.js continuously execute addShard and removeShard and randomly kills some of them. This test is currently running in some suites that have a hook running transitionToDedicated and transitionFromDedicated in the background, so the following scenario could happen:

1. transitionToDedicated starts draining the config.system.sessions collection
2. The destination shard of the migration is removed and added with the same id

This makes the dropCollection in addShard to drop the recently migrated collection, causing a consistency issue. This is not a problem that users would encounter, it is the result of rapidly removing and adding the same shard with the same id, so we should blacklist the test from suites that perform add/remove shard in the background.