Clarify note for using exceptions in QueryBuilder docs

[sypets]

The exception type is a \Doctrine\DBAL\DBALException which can be caught and transferred to a better error message if the application has to expect query errors. Note this is not good habit and often indicates an architectural flaw of the application at a different layer.

https://docs.typo3.org/m/typo3/reference-coreapi/master/en-us/ApiOverview/Database/TipsAndTricks/Index.html

If someone knows this and knows what is better practices, they probably do not need this note. If someone does not, it might be helpful to write what would be a better practice and possibly link to more information.