Remove the deprecated method Environment.getBytecodeProvider(), ensuring all choices related to the BytecodeProvider are fully scoped into each SessionFactory instance.

This effectively makes it possible to use a different BytecodeProvider in each SessionFactory, something which previosly wasn’t possible. A potential follow-up could be to physically separate the BytecodeProvider implementations into an optional jar, and make implementations pluggable/swappable; for GraalVM it’s useful to be able to run the system without actually having any of them reachable.

This is a follow-up to https://hibernate.atlassian.net/browse/HHH-12194