SQL-Ressources and the `use_ssl` switch

[RincewindsHat]

Describe the bug

While deploying a new setup we encountered problems with MySQL-Databases
which enforced TLS.
According to this comment
the use_ssl switch does not at all I would have guessed what it does
(forcefully enable TLS or forcefully disable TLS), but is only "decorartion" regarding
the database connection parameters.

I think this is misleading.

To Reproduce

1. Install a new Icinga Web 2 setup
2. Add database ressource which point to SQL databases which enforce TLS
3. Install Icinga Director too
4. Try to get all of this working

Expected behavior

I would expect the use_ssl switch to either enforce TLS or disable it completely.
And that different modules (especially "official" ones (like the director)) to show the same behaviour so all of them have the same behaviour.