Parker Quartet; Kim Kashkashian, viola György Kurtág: Six moments musicaux; Officium breve Antonin Dvořák: String Quintet op. 97 ECM Records   The Czech composer Antonin Dvořák (1844-1901) and Hungarian composer György Kurtág (1926-) are seldom mentioned in the same breath. One is more often likely to hear Dvořák being discussed in relation to his older colleague Johannes Brahms, and a similar pairing might be made between Kurtág and György Ligeti. However, they are paired by the Parker Quartet and violist Kim Kashkashian on a 2021 ECM CD.    While their musical languages are worlds apart, connections between Dvořák and Kurtág,