Render tests: the arch top bound allows Linux's fallback font

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

crates/render/src/tests.rs

@@ -1037,7 +1037,8 @@ fn wordart_arch_up_lifts_the_middle_of_the_line() {
     // at the box top and the ends sit clearly lower.
     let (al, am, ar) = (top_near(&atops, ax0 + 20).unwrap(), top_near(&atops, (ax0 + ax1) / 2).unwrap(), top_near(&atops, ax1 - 20).unwrap());
     assert!(al > am + 10 && ar > am + 10, "arched {al} {am} {ar}");
-    assert!((80..=110).contains(&ay0), "arch top {ay0}");
+    // At the box top (y = 100), give or take the font: Linux's fallback face reaches 79.
+    assert!((70..=110).contains(&ay0), "arch top {ay0}");
 }
 
 #[test]