Logs show plaintext redis password when there's connection errors

[david-martin]

e.g.

Limitador Server v1.4.0 (e75ae554) [] release
Failed to connect to Redis at redis://default:<my_plaintext_password>@private-db-redis-ams3-02739-do-user-732691-0.a.db.ondigitalocean.com:25061: Multiplexed connection driver unexpectedly terminated- IoError