Remove Hibernate substitutions and deprecated properties usage

This commit raises the baseline to Hibernate 6.5 for native support,
which allows to remove remaining Hibernate substitutions as well as
deprecated properties usage.

Closes spring-projectsgh-32314

spring-orm/src/main/java/org/springframework/orm/jpa/vendor/SpringHibernateJpaPersistenceProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,7 +24,6 @@
 import jakarta.persistence.spi.PersistenceUnitInfo;
 import org.hibernate.bytecode.enhance.spi.EnhancementContext;
 import org.hibernate.cfg.Configuration;
-import org.hibernate.cfg.Environment;
 import org.hibernate.jpa.HibernatePersistenceProvider;
 import org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl;
 import org.hibernate.jpa.boot.internal.PersistenceUnitInfoDescriptor;
@@ -43,16 +42,8 @@
  * @since 4.1
  * @see Configuration#addPackage
  */
-@SuppressWarnings("removal")  // for Environment properties on Hibernate 6.2
 class SpringHibernateJpaPersistenceProvider extends HibernatePersistenceProvider {
 
-	static {
-		if (NativeDetector.inNativeImage()) {
-			System.setProperty(Environment.BYTECODE_PROVIDER, Environment.BYTECODE_PROVIDER_NAME_NONE);
-			System.setProperty(Environment.USE_REFLECTION_OPTIMIZER, Boolean.FALSE.toString());
-		}
-	}
-
 	@Override
 	@SuppressWarnings({"rawtypes", "unchecked"})  // on Hibernate 6
 	public EntityManagerFactory createContainerEntityManagerFactory(PersistenceUnitInfo info, Map properties) {