Update labels.json

labels.json

@@ -1 +1 @@
-["pre-1900","1900–1945","1946–1990","1991–2008","2009–2015","2016–2018","2019–2022","2023–present"]
+["pre-1900", "1900\u20131945", "1946\u20131990", "1991\u20132008", "2009\u20132015", "2016\u20132018", "2019\u20132022", "2023\u2013present"]