Change Ordering of SASLMechanisms

[geraldurbas]

Want bw. Needed to change the ordering for SASL Mechanism...

Providers Mailserver seems to report PLAIN and LOGIN. But accepted no PLAIN:
so code failed...

But think its better to ry LOGIN first neither

[akhil1508]

@the-djmaze This PR's changes cause issues sending emails with SASL login using OAUTHBEARER as the $type that is selected is always set to LOGIN.

Also, it seems to me the changes here basically make sure only the 'LOGIN' type is selected(regardless of what we want to use) always as we check the first possible type and break over here.

[akhil1508]

@the-djmaze @geraldurbas My suggestion here would be to apply \array_unshift($oSettings->SASLMechanisms, 'LOGIN'); using a beforeLogin hook in a plugin if you want to ensure it gets prioritized and used first in your case.

In any case if the other mechanisms are not supported my your mail server it should default to 'LOGIN' with the change reverted also.