Risky test fix

There is some of the "tests" not testing anything(?)

See the last commit
If I change `$this->any()` to `$this->once()` I'm getting this:
```
1) Cake\Test\TestCase\Network\Email\SmtpTransportTest::testAuthNoAuth
Expectation failed for method name is equal to <string:write> when invoked 1 time(s).
Method was expected to be called 1 times, actually called 0 times.
```