OGM-642 Avoiding read prior to insert if possible

Adding new method `getDuplicateInsertPreventionStrategy()`on `GridDialect`. By default, we do the explicit look-up as before, but of the store itself can detect the situation, we rely on that and omit the additional read.
> So I consider it just as a "marker" for now, but if you feel strongly about it, I can remove the super-type for now and we re-add it later on if required.

Yes, please. Let's remove it for now. It is going to be very easy to add it later if we need it