Tests failing randomly

Tests are currently failing randomly, need to debug this issue.

There are scenarios where it is passing and then randomly failing. For example:
Passed test: https://travis-ci.org/EasyEngine/easyengine/builds/433394695?utm_source=github_status&utm_medium=notification
Failed test: https://travis-ci.org/EasyEngine/easyengine/builds/434077615?utm_source=github_status&utm_medium=notification

The Exception in redis cache test site is randomly occurring, it is giving HTTP code `302` instead of `200` OK. This could be happening due to multisite installations in the tests.

The generated exception:

```
Unable to find HTTP/1.1 200 OK
Actual output is : HTTP/1.1 302 Found
Server: nginx
Date: Fri, 28 Sep 2018 09:18:55 GMT
Content-Type: text/html; charset=UTF-8
Connection: keep-alive
X-Powered-By: PHP/7.2.9
Location: http://wpsubdom.test/wp-signup.php?new=wpcache.test
X-SRCache-Fetch-Status: MISS
X-SRCache-Store-Status: BYPASS
X-Powered-By: EasyEngine

(Exception)
```