[CLIENT] Removed the monkeypatch for Typhoeus in tests

The `NameError - no member 'client_cert_passwd' in struct:` error has been fixed in Typhoeus 0.6.8.

Related: typhoeus/typhoeus#346, lostisland/faraday/pull/323, lostisland/faraday/pull/335

Related: adc4810, 4aeded6