Spring Remove MediaType::sortByQualityValue

MediaType::sortByQualityValue is not used by Spring Framework itself, nor does it appear to be used by any Spring projects. Let's remove the method in 6.0 and deprecate it in 5.3.11.

Comment From: poutsma

The comparator used by MediaType::sortByQualityValue is in fact still used by MediaType::sortBySpecificityAndQuality. Closing as invalid.