Creates a representation of this entry as an {@link org.infinispan.container.entries.InternalCacheValue}. The main purpose of this is to provide a representation that does
not have a reference to the key. This is useful in situations where the key is already known or stored elsewhere, making serialization and deserialization more efficient.
Note that this should not be used to optimize memory overhead, since the saving of an additional reference to a key (a single object reference) does not warrant the cost of constructing an InternalCacheValue. This
only makes sense when marshalling is involved, since the cost of marshalling the key again can be sidestepped using an InternalCacheValue if the key is already known/marshalled.
@return a new InternalCacheValue encapsulating this InternalCacheEntry's value and expiration information.