Add missing proxy hints to support multi document transactions.

[christophstrobl]

hints.proxies().registerJdkProxy(com.mongodb.client.MongoDatabase.class,
		org.springframework.aop.SpringProxy.class, org.springframework.core.DecoratingProxy.class);
hints.proxies().registerJdkProxy(com.mongodb.client.MongoCollection.class,
		org.springframework.aop.SpringProxy.class, org.springframework.core.DecoratingProxy.class);