Related to:

 - !2223
 - !2203

We were seeing a bunch of `Unable to reassociate connection` -> `Socket reassociation failed`
errors in the logs.

```
Unable to reassociate connection or update last access:
StatusError: Socket reassociation failed.
	at /opt/gitter/gitter-webapp/modules/presence/lib/presence-engine.js:336:17
	at tryCatcher (/opt/gitter/gitter-webapp/node_modules/ioredis/node_modules/bluebird/js/main/util.js:26:23)
	at Promise._settlePromiseFromHandler (/opt/gitter/gitter-webapp/node_modules/ioredis/node_modules/bluebird/js/main/promise.js:508:31)
	at Promise._settlePromiseAt (/opt/gitter/gitter-webapp/node_modules/ioredis/node_modules/bluebird/js/main/promise.js:584:18)
	at Promise._settlePromises (/opt/gitter/gitter-webapp/node_modules/ioredis/node_modules/bluebird/js/main/promise.js:700:14)
	at Async._drainQueue (/opt/gitter/gitter-webapp/node_modules/ioredis/node_modules/bluebird/js/main/async.js:123:16)
	at Async._drainQueues (/opt/gitter/gitter-webapp/node_modules/ioredis/node_modules/bluebird/js/main/async.js:133:10)
	at Immediate.Async.drainQueues [as _onImmediate] (/opt/gitter/gitter-webapp/node_modules/ioredis/node_modules/bluebird/js/main/async.js:15:14)
	at processImmediate (internal/timers.js:461:21)
```