Add DelayMs type for settings (#40659)

Closes #40610

Release Notes:

- N/A

crates/diagnostics/src/diagnostics_tests.rs

@@ -1341,7 +1341,7 @@ async fn test_hover_diagnostic_and_info_popovers(cx: &mut gpui::TestAppContext)
             range: Some(range),
         }))
     });
-    let delay = cx.update(|_, cx| EditorSettings::get_global(cx).hover_popover_delay + 1);
+    let delay = cx.update(|_, cx| EditorSettings::get_global(cx).hover_popover_delay.0 + 1);
     cx.background_executor
         .advance_clock(Duration::from_millis(delay));