Use Crimson Text as heading font family (#6985)

verso/theme.json

@@ -520,7 +520,7 @@
 			},
 			"heading": {
 				"typography": {
-					"fontFamily": "var(--wp--preset--font-family--rubik)",
+					"fontFamily": "var:preset|font-family|crimson-text",
 					"fontWeight": "400",
 					"lineHeight": "1.125"
 				}