fix post title typography (#6169)

* fix post title typography

* unset lineHeight for core/post-title and add it to h2 element

Co-authored-by: Matias Benedetto <matias.benedetto@gmail.com>

pendant/theme.json

@@ -308,7 +308,8 @@
 				"typography": {
 					"fontFamily": "var(--wp--preset--font-family--heading-font)",
 					"fontSize": "clamp(3rem, 6vw, 5rem)",
-					"fontWeight": 400
+					"fontWeight": 400,
+					"lineHeight": 1
 				}
 			},
 			"h3": {