[hibernate-dev] Make JpaCompliance available earlier

I am working on HHH-12282. I was thinking that the best solution would be to check this setting at the time when Join#setOptional is called. The reason being to centralize the place that this check needs to be done. I can do it inside the persister as it consumes the Join, but that leads to duplicated code. But in order to fix in the way I just described, we would have to make JpaCompliance available earlier in the boot process (currently it is built as part of SessionFactoryOptions/Builder). WDYT?